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diminishes, while the subject thinks he is writing nor water." Though Aden is not so entirely destitute faster.

of vegetation as this famous traveller supposed, the The pressure curves obtained from children differ impression it produced upon much more recent botanifrom all the adult types. A flat-topped curve had cal visitors was scarcely more favourable. Sir J. D. been considered until recently the characteristic child's Hooker, in 1847, described Aden as being "upon the curve (Fig. 3, II.a). This curve does not, however, whole the ugliest, blackest, most desolate, and most represent the first stage in the acquiring of writing. dislocated piece of land, of its size, that ever I set The first curves obtained are more or less character- eyes upon, and I have seen a good many ugly places”; istically drawing curves (Fig. 3, I.). Such curves are but he mentioned the comparatively fertile lower best seen where the child begins with printed letters valleys, thickly studded with beautiful-flowered shrubs rather than script (Fig. 3, 1.c). In this case each and small trees. Prof. Blatter's compilation is based stroke requires a definite and separate impulse, and largely upon the scattered reports and collections this is well marked in the pressure curve. In the made by residents and visitors, and shows that Aden, earliest script the curve seems merely irregular, but despite the fact that it consists largely of “bare naked this is due to variations in the drawing unit with rocks which cannot find their equal in any part of the which the child is dealing, which may be a single world as regards dryness, infernal heat, and barrenstroke, a letter, or a group of letters. The second ness,” possesses an interesting and surprisingly varied stage in learning to write is marked by what was vegetation. formerly called the child type of pressure curve, a The volcanic rocks forming the greater part of the curve with a strikingly regular, flat top, which is Aden peninsula, which is about fifteen miles in circumstill a drawing curve, though the child is now draw- ference, are practically devoid of plant life; even ing the whole word. This curve passes gradually lichens are scarce on the sun-baked and disintegrating into the curve with rippled top of adult writing, the rock-surfaces. These lofty and jagged rocks, rising in time when the transition can really be said to take places to 1700 ft. altitude, are scored by steep gulleys place being about the age of ten or eleven (Fig. 3, and mostly run straight down to the shore, but here III.). The transition seems to mean two things. In and there the lower slopes are gentle or almost flat, the first place the necessary co-ordinations are estab- and in such places the clayey soil retains rain-wash, lished to such an extent that the mechanism of writ- which elsewhere quickly runs off or percolates through ing works without attention to the individual strokes the loose soil, and the vegetation in these parts is and forms which the hand is making. In the second fairly rich. Apart from such habitats, the rigorous place, and partly because of this, writing has ceased character of the conditions with which the Aden to be drawing and has become language, the rhythm- plants have to contend may be realised from the facts ical variations in point pressure corresponding to that there are no permanent streams or springs or the rhythmical variations in grip pressure, and being marshes or ponds; the annual rainfall rarely exceeds analogous to a certain extent to the rhythm of speech. six or seven inches in the wettest years; no rain may When this stage is reached the impulse under the fall for two years at a time, and when it does fall direction of which writing takes place is distinctly a it usually comes down in a torrent lasting for a day word impulse, and sometimes even a phrase or sen- two, changing the dry gulleys into turbulent tence impulse.

streams which quickly dry up again. It has also been found that the writing of defectives The Aden flora consists of 250 species of flowering fails to show this characteristic rhythm of adult writ- plants, including ten trees, fifty-eight shrubs, forty-six ing, while drugs like alcohol tend to impair the undershrubs, and 136 herbs. The work of the rhythm and ultimately to break it down altogether, Carnegie Institution botanists has shown that in the apparently because of their effect on co-ordination.. most arid regions of the earth, where the rainfall is It is also somewhat interesting to find that the pres- extremely scanty, infrequent and irregular, what were sure curve is almost as characteristic of an individual formerly regarded as the typical desert-plants, namely, as his signature, and persists even in left-hand writing species with fleshy water-storing leaves and stems without previous practice. There is evidently a wide (cacti, etc.), are almost or entirely absent, and that field for investigation in this direction, and perhaps the desert type par excellence is not succulent, but we may yet see the development of a real science of sclerophyllous. This term is applied to plants which graphology based upon such investigation.

do not store up water but contend with the extreme aridity of their environment by various adaptations

for reducing water-loss to a minimum-reduced leaf FLORA OF ADEN.1

surface, dense hair-covering, waxy cuticle, gummy PROF. BLATTER has brought together an inter- epidermis

, development of leaves or branches or both esting account of the vegetation of the Aden

From Prof. Blatter's iist such plants peninsula, in which, after summarising the history of

appear to be dominant in the vegetation of Aden; botanical exploration of this region from the earliest

fleshy species are practically confined to the seatimes, he gives data regarding physiography, climate,

coast. A further point of interest is that about half soils, tabulated lists of the plants, and brief notes on

of the herbaceous plants listed for Aden are short. their distribution, origin, means of dispersal, etc. No

lived annuals, which grow in the clayey soil of the references are made to work on plant ecology, but a

flats and gentle slopes where water can be retained comparison of the characters of the Aden vegetation

in the surface layers long enough for these plants to with that of other arid regions, as investigated par

complete their brief life-cycle whenever rain comes. ticularly by the Carnegie Institution botanical staff

This, again, is a characteristic feature of the typical in North American and North African deserts, brings

desert flora with clayey oases. out some points of considerable ecological interest.

The records of the Botanical Survey of India conThe first botanical description of Aden was given

tain so much that is, at any rate potentially, of general by Ibn Batuta in about 1330, and it consisted of the

interest to students of plant ecology, that while the brief statement that “there are neither seeds nor trees

material they contain is welcome and useful, it is | “The Flora of Aden." By Ethelbert Blatter, Professor of Botany at

much to be hoped that the survey workers will make St. Xavier's College, Bombay. Records of the Botanical Survey of India.

themselves acquainted with what has been and is being Vol. vii, No. 1, Calcutta, 1914. Pp. ii+79; 5 plates ; 1 map.

done on modern ecological lines, so that they may

or

correlate their results with those obtained in other

According to the report in the January number of regions by the application of methods which alone the Emu, the fourteenth annual session of the Royal can make a botanical survey what it is now generally Australasian Ornithologists' Union, held in Melexpected to be-a correlated study of the plant com- bourne in November, 1914, was a thorough success, munities and the plant habitats of the area surveyed. a number of interesting excursions being taken and

F. Ć.

several papers read. In the same issue Mr. A. J. Campbell directs attention to the apparent extermina

tion of three beautifully coloured species of parrotsORNITHOLOGICAL NOTES.

namely, the scarlet-shouldered Pse photus pulcherrimus, AT T the annual meeting of the Royal Society for the the chestnut-shouldered grass-parrot (Euphema pul

Protection of Birds, held at the Middlesex chella), and the night-parrot (Geopsittacus occi. Guildhall, on March 11, when the Ranee of Sarawak dentalis), all of which were to be met with a few presided, an optimistic tone prevailed in the first years ago in Queensland or the neighbouring districts. portion of the report for 1914, as several of the schemes Their disappearance is attributed to domesticated cats and objects for which the Society had long been run wild, aided by bush-fires and the spread of cultivalabouring were apparently on the point of realisation. tion. Then came the war, when all these fair prospects- In the Zoologist for March, Prof. J. C. Patten particularly the expected passing of the Government describes an immature aquatic warbler picked up at Plumage Bill-were dissipated, to be renewed, it may Tuskar light-station, County Wexford, on August 9, be hoped, at the conclusion of the war. In other 1913. The paper is illustrated by a plate showing respects the work of the Society was, on the whole, how the plumage of this species differs from that of satisfactory; but finance is a matter on which there the sedge-warbler at the same age. In the aquatic is serious ground for anxiety, as a falling-off in warbler the back is marked by streaks of black and subscriptions during the current year is almost inevi- buff, which are but slightly developed in the sedge. table.

warbler; both webs of the middle pair of tail-feathers The condor forms the subject of the first article in are also margined with buff, and all the tail-feathers the March number of the Children's Museum News, are likewise longer, narrower, and more pointed than where particular reference is made to the long period those of the sedge-warbler. The Tuskar bird is the taken by these birds to attain the adult plumage. second of its kind taken in Ireland; the number of Hatched during the height of the southern summer, specimens recorded from Great Britain (England) is the young exchange their white nestling dress for seventeen. a uniformly brown garb, which is not finally discarded

R. L. until the seventh year, in February or the early part of March. Although able to fly when a year old,

MOUNTAIN GEOLOGY. young condors do not leave their parents until the completion of their third year.

IN

N the Mémoires de la Société de Physique et d'HisIn the course of a wonderfully illustrated article on toire Naturelle de Genève (vol. xxxviii., pages a breeding-colony of buff-backed herons, published in 69–168) M. Louis Duparc and Mme. M. Tikanowitch the March issue of Wild Life, Mr. B. Beetham directs continue their work on the Ural Chain by an account attention to the small size of the nests of these birds, of its rocks to the east of the main watershed and in the which alone renders it possible for so many to be upper basin of the rivers Kakwa and Wagran. This, crowded into a single bush. So heavily weighted, the fourth of their contributions to the geology of that indeed, are some of the boughs that they hang almost chain, is prefaced by a sketch of the physical features vertically; and it is little short of marvellous how the of the district, the illustrations to which show that it eggs and young are retained in the shallow, cup-like consists of huge hills rather than of rugged mounnests, generally overhanging a lagoon, into which the tains. The rocks are partly sedimentary, arenaceous, hapless offspring may be precipitated by a gust of or slaty argillaceous, with some quartzose crystalline greater strength than usual. The nests are devoid of schists; partly igneous. Of the latter a very complete lining, and in some cases so flimsy in structure that petrographical study has been made, including chemthe pale blue eggs are visible from below.

ical analyses of the principal types, several of which The nesting-habits of fulmar-petrels on a precipitous are very interesting. Among those of deep-seated cliff in the Orkneys form the subject of an article by origin are the following: quartz-bearing micaceous Mr. O. G. Pike in British Birds for March. The diorites (evidently allied to tonalites) and gabbroauthor arrived on the scene in the second week in diorites (in which probably the hornblende is second. July, when most of the young were hatched; but he ary), olivine-gabbros, and massive dunites. Besides was able to secure a couple of photographs of sitting these and serpentines, are tilaite (a variety of eucrite) birds, as well as one of a downy nestling. Each and pyroxenites. This association is interesting, for it female lays but a single egg, and at a very early often exists, more or less completely, in other regions, stage the young bird is capable of indulging in the and suggests certain modes of magmatic differentiadistinctly petrel-trait of discharging a forceful jet of tion. The dyke-rocks include hornblendic berbachites evil-smelling green oil from its mouth in the face of a and various dioritic porphyrites, besides amphibolites, real or supposed enemy.

in some at least of which the hornblende appears to To the Journal of the Straits Branch of the Royal be secondary. The article ends with a description of Asiatic Society for December, 1914, Mr. I. C. Moulton, the crystalline schists which, however, do not appear curator of the Sarawak Museum, contributes a list of to be of any unusual interest. The memoir, illus. Bornean birds. In an appendix to Hugh Low's trated by twelve photographic figures of the micro

Sarawak," published in 1848, the number of species scopic structure of the more interesting rocks, forms a then recognised was fifty-nine; this was raised in most welcome addition to petrology, the more remark1889 in a list drawn up by the late Mr. A. H. Everett able when we learn the difficulties with which the to 536 (exclusive of thirty-four from Palawan), while authors had to contend in their three visits to this in the present list the number is again augmented to region, in consequence of the sparse population, the 555; and this, too, despite the fact that several birds want of roads, and the absence of maps. formerly regarded as distinct species have been rele- In the next fascicule (pp. 169-98) M. Jules Favre gated to the rank of local races.

describes the relation of the plant-life to the geology

a

of the Salève. This mountain, which rises about surfaces, result in features of such clearly differ3000 ft. above Geneva, consists of limestones and entiated character that no unbiassed observer can fail shales (Upper Jurassic and Neocomian), with Middle to recognise their great significance and value. When Tertiary sandstones, chiefly molasse, and glacial de- we find long, narrow, deep, and winding inlets from posits. Apart from the effects of altitude, the flora is the sea into the land ("* fiords," etc.), it is obvious much affected by the nature of the rock on which it that such features could not result from the cutting grows, and besides this, a small colony of special back of the coast-line by the sea, but that they are plants generally accompanies any local physical pecu- old river-channels that have been drowned by the larity. Of this association the large erratics of sinking of the land. On the other hand, sea-beaches, Alpine granite and schists afford a remarkable instance. with caves, fan-taluses, and other signs of shore Asplenium septentrionale is the only phanerogamous work, occurring at various heights above the present plant found on them to which rocks, in the High sea-level, speak, quite as unmistakably, of elevation Alps, it is practically restricted.

having taken place.

The illustrious American geologist, James Dwight BLOOD-PARASITES AND

Dana, .when accompanying the United States ExplorFLEAS.

ing Expedition under Wilkes, had the opportunity

of visiting many coral-reef islands, and we are inJ. D. Thomson have been engaged upon the inves- debted to him for first showing, in 1849, the value tigation of the rat trypanosome, Trypanosoma lewisi,

of the evidence afforded by coast-lines, where bounded with special reference to its relation to the rat flea, by “encircling” or “barrier" reefs, of subsidence Ceratophyllus fasciatus. The results of this laborious having taken place. These valuable observations of and painstaking research are now published in the Dana seem to have been almost completely overQuarterly Journal of Microscopical Science. They

looked until quite recent years, and it is only fitting form i comprehensive monograph which occupies the that to a fellow-countryman of his should fall the whole of the last part of this journal (vol. lx., task of recalling and developing this pioneer work.. part 4) and will undoubtedly be a standard work of Where a coral-reef encircles a land-mass it is evident reference for students of these very important blood- that the presence of "fiords” or their equivalents in parasites. The fact that the authors have dissected the central island supplies clear evidence of submergand examined more than 1600 fleas in the course of ence having taken place, though possibly this may their investigations shows the thoroughness with

not be the latest of the movements that have occurred. which the work has been carried out, while the artis

On the other hand, the existence of islands composed tic treatment and accuracy of detaii contributed by of upraised coral-rock, with sea-caves and shore dethe illustrations, for which due acknowledgment is posits at different stageș, up to more than 1000 ft. made to Miss Rhodes, leave nothing to be desired. above the present sea-level, supplies equally clear T. lewisi is fortunately a non-pathogenic parasite, at

evidence of movements in an opposite direction having any rate so far as the rat is concerned, and it cannot taken place. The late Prof. Alexander Agassiz publive at all in human blood. It therefore forms a much lished a very valuable series of reports, abundantly more suitable type for general study than such deadly illustrated, concerning these upraised Pacific reefs, species as those which are conveyed by the tsetse-fly and we now have the promise of equally important in Africa, and are responsible for fly-disease amongst descriptions by Prof. W. M. Davis, also of Harvard, horses and cattle, and for sleeping sickness in human of the cases in which the proofs of subsidences can beings. The authors give a very useful account of be no less satisfactorily made out. the technique employed in their investigations, and, The general result to which these various observaincidentally, throw a good deal of light upon details tions appear to point is that, over the whole area of of the anatomy and histology of the flea.

the Pacific, areas of elevation and others of subsiThe flea, of course, receives the parasite with the dence can be clearly traced, though the movements blood which it extracts from the rat, but apparently it were often interrupted and sometimes reversed; nevercannot infect the rat by inoculating trypanosomes into theless, it must be admitted that in some cases the it through the proboscis. The rat is supposed to evidence seems puzzling and contradictory-islands become infected through the mouth; in the process of with clear evidence of elevation lying in close licking its fur it takes in trypanosomes with fæcal proximity to others which have clearly subsided. matter deposited by the flea; or it may become insected Geologists will not, however, be unprepared for the by eating infected fleas.

occurrence of such seeming anomalies; they will only While in the flea the trypanosome is confined recognise that, eventually, actual fault-lines may be throughout its whole development to the digestive traced by such means in the oceanic areas. At the same tract, where it undergoes extensive asexual multiplica- time it may be well to bear in mind the caution sugtion and passes through a number of more or less gested by Darwin in his correspondence with Semper distinct phases, some of which are intracellular in the that, however clear may be the evidence in favour of epithelium of the stomach. No sexual phenomena any special theory of coral-reef formation, we must have been detected, and the authors agree with Miss be always prepared for the occurrence of special cases Robertson that such phenomena have not as yet been which can only be accounted for by the operation of satisfactorily demonstrated in the case of any trypano- exceptional causes. The full and complete accountsome.

which will no doubt be sufficiently illustrated-of

Prof. W. M. Davis's important series of explorations CHANGES OF RELATIVE LEVELS OF:

will be looked forward to with special interest, and

in the meantime the subjoined general summary of LAND AND SEA.

his results will be welcomed by all naturalists. MONG the different kinds of evidence showing

J. W. J. A

that changes in the relative levels of sea and land are going on all over the globe, the forms

Preliminary Report on a Shaler Memorial Study of assumed by coast-lines are now recognised by geo

Coral Reefs. logists as being the most convincing and satisfactory. A liberal grant from the Shaler Memorial Fund of Sea-erosion, acting only along shore-lines, and sub- Harvard University, supplemented by a generous subaerial denudation, operating over the whole land- sidy from the British Association for the Advancecorrelate their results with those obtained in other According to the report in the January number of regions by the application of methods which alone the Emu, the fourteenth annual session of the Royal can make a botanical survey what it is now generally Australasian Ornithologists' Union, held in Melexpected to be--a correlated study of the plant com- bourne in November, 1914, was a thorough success, munities and the plant habitats of the area surveyed. a number of interesting excursions being taken and

F. C.

several papers read. In the same issue Mr. A. J. Campbell directs attention to the apparent extermina

tion of three beautifully coloured species of parrotsORNITHOLOGICAL NOTES.

namely, the scarlet-shouldered Psephotus pulcherrimus, AL T the annual meeting of the Royal Society for the the chestnut-shouldered grass-parrot (Euphema pul

Protection of Birds, held at the Middlesex chella), and the night-parrot (Geopsittacus occi. Guildhall, on March 11, when the Ranee of Sarawak dentalis), all of which were to be met with a few presided, an optimistic tone prevailed in the first years ago in Queensland or the neighbouring districts. portion of the report for 1914, as several of the schemes Their disappearance is attributed to domesticated cats and objects for which the Society had long been run wild, aided by bush-fires and the spread of cultivalabouring were apparently on the point of realisation. tion. Then came the war, when all these fair prospects- In the Zoologist for March, Prof. J. C. Patten particularly the expected passing of the Government describes an immature aquatic warbler picked up at Plumage Bill-were dissipated, to be renewed, it may Tuskar light-station, County Wexford, on August 9, be hoped, at the conclusion of the war. In other 1913. The paper is illustrated by a plate showing respects the work of the Society was, on the whole, how the plumage of this species differs from that of satisfactory; but finance is a matter on which there the sedge-warbler at the same age. In the aquatic is serious ground for anxiety, as a falling-off in warbler the back is marked by streaks of black and subscriptions during the current year is almost inevi- buff, which are but slightly developed in the sedge. table.

warbler; both webs of the middle pair of tail-feathers The condor forms the subject of the first article in are also margined with buff, and all the tail-feathers the March number of the Children's Museum News, are likewise longer, narrower, and more pointed than where particular reference is made to the long period those of the sedge-warbler. The Tuskar bird is the taken by these birds to attain the adult plumage. second of its kind taken in Ireland; the number of Hatched during the height of the southern summer, specimens recorded from Great Britain (England) is the young exchange their white nestling dress for seventeen. a uniformly brown garb, which is not finally discarded

R. L. until the seventh year, in February or the early part of March. Although able to fly when a year old,

MOUNTAIN GEOLOGY.
young condors do not leave their parents until the
completion of their third year.

IN
N the Mémoires de la Société de Physique et d’His-

toire Naturelle de Genève (vol. xxxviii., pages a breeding-colony of buff-backed herons, published in 69–168) M. Louis Duparc and Mme. M. Tikanowitch the March issue of Wild Life, Mr. B. Beetham directs

continue their work on the Ural Chain by an account attention to the small size of the nests of these birds, of its rocks to the east of the main watershed and in the which alone renders it possible for so many to be upper basin of the rivers Kakwa and Wagran. This, crowded into a single bush. So heavily weighted, the fourth of their contributions to the geology of that indeed, are some of the boughs that they hang almost chain, is prefaced by a sketch of the physical features vertically; and it is little short of marvellous how the of the district, the illustrations to which show that it eggs and young are retained in the shallow, cup-like consists of huge hills rather than of rugged mounnests, generally overhanging a lagoon, into which the tains. The rocks are partly sedimentary, arenaceous, hapless offspring may be precipitated by a gust of or slaty argillaceous, with some quartzose crystalline greater strength than usual. The nests are devoid of schists; partly igneous. Of the latter a very complete lining, and in some cases so flimsy in structure that petrographical study has been made, including chemthe pale blue eggs are visible from below.

ical analyses of the principal types, several of which The nesting-habits of fulmar-petrels on a precipitous are very interesting. Among those of deep-seated cliff in the Orkneys form the subject of an article by origin are the following: quartz-bearing micaceous Mr. O. G. Pike in British Birds for March. The diorites (evidently allied to tonalites) and gabbroauthor arrived on the scene in the second week in diorites (in which probably the hornblende is second. July, when most of the young were hatched; but he ary), olivine-gabbros, and massive dunites. Besides was able to secure a couple of photographs of sitting these and serpentines, are tilaite (a variety of eucrite) birds, as well as one of a downy nestling. Each and pyroxenites. This association is interesting, for it female lays but a single egg, and at a very early often exists, more or less completely, in other regions, stage the young bird is capable of indulging in the and suggests certain modes of magmatic differentiadistinctly petrel-trait of discharging a forceful jet of tion. The dyke-rocks include hornblendic berbachites evil-smelling green oil from its mouth in the face of a and various dioritic porphyrites, besides amphibolites, real or supposed enemy.

in some at least of which the hornblende appears to To the Journal of the Straits Branch of the Royal be secondary. The article ends with a description of Asiatic Society for December, 1914, Mr. J. C. Moulton, the crystalline schists which, however, do not appear curator of the Sarawak Museum, contributes a list of to be of any unusual interest. The memoir, illus. Bornean birds. In an appendix to Hugh Low's trated by twelve photographic figures of the micro“Sarawak,” published in 1848, the number of species scopic structure of the more interesting rocks, forms a then recognised was fifty-nine; this was raised in most welcome addition to petrology, the more remark1889 in a list drawn up by the late Mr. A. H. Everett able when we learn the difficulties with which the to 536 (exclusive of thirty-four from Palawan), while authors had to contend in their three visits to this in the present list the number is again augmented to region, in consequence of the sparse population, the 555; and this, too, despite the fact that several birds want of roads, and the absence of maps. formerly regarded as distinct species have been rele- In the next fascicule (pp. 169-98) M. Jules Favre gated to the rank of local races.

describes the relation of the plant-life to the geology

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of the Salève. This mountain, which rises about surfaces, result in features of such clearly differ3000 ft. above Geneva, consists of limestones and entiated character that no unbiassed observer can fail shales (Upper Jurassic and Neocomian), with Middle to recognise their great significance and value. When Tertiary sandstones, chiefly molasse, and glacial de- we find long, narrow, deep, and winding inlets from posits. Apart from the effects of altitude, the flora is the sea into the land (“fiords,” etc.), it is obvious much affected by the nature of the rock on which it that such features could not result from the cutting grows, and besides this, a small colony of special back of the coast-line by the sea, but that they are plants generally accompanies any local physical pecu- old river-channels that have been drowned by the larity. Of this association the large erratics of sinking of the land. On the other hand, sea-beaches, Alpine granite and schists afford a remarkable instance. with caves, fan-taluses, and other signs of shore Asplenium septentrionale is the only phanerogamous work, occurring at various heights above the present plant found on them to which rocks, in the High sea-level, speak, quite as unmistakably, of elevation Alps, it is practically restricted.

having taken place.

The illustrious American geologist, James Dwight BLOOD-PARASITES

Dana, .when accompanying the United States ExplorAND FLEAS.

ing Expedition under Wilkes, had the opportunity FOR OR the past five years Prof. E. A. Minchin and Dr. of visiting many coral-reef islands, and we are inJ. D. Thomson have been engaged upon the inves

debted to him for first showing, in 1849, the value tigation of the rat trypanosome, Trypanosoma lewisi,

of the evidence afforded by coast-lines, where bounded with special reference to its relation to the rat flea, by “encircling” or “barrier" reefs, of subsidence Ceratophyllus fasciatus. The results of this laborious having taken place. These valuable observations of and painstaking research are now published in the

Dana seem to have been almost completely overQuarterly Journal of Microscopical Science. They looked until quite recent years, and it is only fitting form a comprehensive monograph which occupies the that to a fellow-countryman of his should fall the whole of the last part of this journal (vol. lx.,

task of recalling and developing this pioneer work. part 4) and will undoubtedly be a standard work of Where a coral-reef encircles a land-mass it is evident reference for students of these very important blood- that the presence of “fiords" or their equivalents in parasites. The fact that the authors have dissected the central island supplies clear evidence of submergand examined more than 1600 fleas in the course of ence having taken place, though possibly this may their investigations shows the thoroughness with

not be the latest of the movements that have occurred. which the work has been carried out, while the artis- On the other hand, the existence of islands composed tic treatment and accuracy of detaii contributed by of upraised coral-rock, with sea-caves and shore dethe illustrations, for which due acknowledgment is posits at different stages, up to more than 1000 ft. made to Miss Rhodes, leave nothing to be desired. above the present sea-level, supplies equally clear T. lewisi is fortunately a non-pathogenic parasite, at

evidence of movements in an opposite direction having any rate so far as the rat is concerned, and it cannot taken place. The late Prof. Alexander Agassiz publive at all in human blood. It therefore forms a much lished a very valuable series of reports, abundantly more suitable type for general study than such deadly illustrated, concerning these upraised Pacific reefs, species as those which are conveyed by the tsetse-fly and we now have the promise of equally important in Africa, and are responsible for fy-disease amongst descriptions by Prof. W. M. Davis, also of Harvard, horses and cattle, and for sleeping sickness in human of the cases in which the proofs of subsidences can beings. The authors give a very useful account of be no less satisfactorily made out. the technique employed in their investigations, and, The general result to which these various observaincidentally, throw a good deal of light upon details tions appear to point is that, over the whole area of of the anatomy and histology of the Hea.

the Pacific, areas of elevation and others of subsiThe flea, of course, receives the parasite with the dence can be clearly traced, though the movements blood which it extracts from the rat, but apparently it were often interrupted and sometimes reversed; nevercannot infect the rat by inoculating trypanosomes into theless, it must be admitted that in some cases the it through the proboscis. The rat is supposed to evidence seems puzzling and contradictory-islands become infected through the mouth; in the process of with clear evidence of elevation lying in close licking its fur it takes in trypanosomes with fæcal proximity to others which have clearly subsided. matter deposited by the flea; or it may become insected Geologists will not, however, be unprepared for the by eating infected fleas.

occurrence of such seeming anomalies; they will only While in the flea the trypanosome is confined recognise that, eventually, actual fault-lines may be throughout its whole development to the digestive traced by such means in the oceanic areas. At the same tract, where it undergoes extensive asexual multiplica- time it may be well to bear in mind the caution sugtion and passes through a number of more or less gested by Darwin in his correspondence with Semper distinct phases, some of which are intracellular in the that, however clear may be the evidence in favour of epithelium of the stomach. No sexual phenomena any special theory of coral-reef formation, we must have been detected, and the authors agree with Miss be always prepared for the occurrence of special cases Robertson that such phenomena have not as yet been which can only be accounted for by the operation of satisfactorily demonstrated in the case of any trypano-exceptional causes. The full and complete account

which will no doubt be sufficiently illustrated--of Prof. W. M. Davis's important series of explorations

will be looked forward to with special interest, and CHANGES OF RELATIVE LEVELS OF. in the meantime the subjoined general summary of LAND AND SEA.

his results will be welcomed by all naturalists. A MONG the different kinds of evidence showing

J. W. J. that changes in the relative levels of sea and land are going on all over the globe, the forms

Preliminary Report on a Shaler Memorial Study of assumed by coast-lines are now recognised by geo

Coral Reefs. logists as being the most convincing and satisfactory. A liberal grant from the Shaler Memorial Fund of Sea-erosion, acting only along shore-lines, and sub- Harvard l'niversity, supplemented by a generous subaerial denudation, operating over the whole land- sidy from the British Association for the Advance

some.

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