Page images
PDF
EPUB

MIERSITE, A CUBIC MODIFICATION OF NATIVE SILVER IODIDE.

SILVER IODIDE is remarkable in being one of the few

substances which undergo a contraction in volume as the temperature increases. This contraction is uniform until about 146° C. is reached, when there is a further sudden contraction of considerable amount, after which the substance expands. The sudden contraction at 146° is accompanied by a change in all the physical properties of the substance, the pale yellow, hexagonal modification which exists at ordinary temperatures, being then changed into a bright yellow, cubic modification. On cooling the reverse phenomena are observed.

From this behaviour it would be expected that only the pale yellow, hexagonal modification would be found as a natural mineral, and as a matter of fact the only pure silver iodide so far known is the hexagonal species iodyrite. The existence of a cubic modification has, however, long been suspected from the Occurrence of iodine in the cubic mineral iodobromite (2AgCl. 2AgBr. AgI). This probably represents the artificial cubic modification which is stable above 146°, in which case the natural crystals of iodobromite should be pseudo-cubic; in fact, pseudomorphs of the hexagonal modification with the external form of the cubic modification. This would be strictly analogous to the pseudo-cubic leucite and boracite, which become isotropic when heated to a definite temperature.

The new mineral, miersite, is, however, quite distinct from these, and proves that silver iodide is trimorphous. The principal characters of the three modifications are :

[blocks in formation]

Iodyrite, in all its crystallographic characters, is practically identical with wurtzite (ZnS), greenockite (CdS), and zincite (ZnO); these are all hexagonal and hemimorphic, possess a basal cleavage, and are optically positive, while the axial ratios vary only very slightly (a: c = 1:08109 1:08196). Many other substances may perhaps be included in this series, e.g. ice, magnesium, cadmium iodide, tridymite (SiO2), &c. In the same way the dimorphous cubic modifications miersite, blende (ZnS), and marshite (CuI) form another parallel series, since they are all exactly alike in crystallographic characters.

It will now be seen that the same relation exists between iodyrite and miersite as exists between wurtzite and blende. This forms, as far as crystallographic characters are concerned, a perfect example of an isodimorphous group, but apparently the only relation existing between zinc sulphide and silver iodide is that their simplest conceivable chemical molecules contain two atoms.

From these somewhat remarkable relations one is inclined to ask why should there not be a third modification of zinc sulphide to correspond with iodobromite? or why should not all these substances (e.g. ice, &c.) be dimorphous or trimorphous to fill up the gaps in these parallel series? Further, if nantokite and marshite are to be represented by the formulæ CuCl, and Cu,I, respectively, then miersite should be Agal, these double molecules, however, only depend on the vapour density of cuprous chloride, but the gaseous molecule cannot be the same as the crystal molecule, especially when there are, as in silver iodide, possibly three types of the latter.

:

A detailed description of miersite will be published in the Mineralogical Magazine. It may now be mentioned that the

two specimens preserved in the British Museum collection are from the Broken Hill silver mines in New South Wales; the associated minerals on one specimen are quartz, copper glance, and garnet, and on the other, malachite, wad and anglesite. The small crystals of miersite, which do not exceed 2 mm. in diameter, are scattered over the surface of the matrix; they are of a pale or bright yellow colour, with an adamantine lustre. The only forms present are the cube and one or both of the tetrahedra, the latter usually differing in size but not in surface characters. In many respects the mineral is strikingly similar to the yellow blende which occurs in the white dolomite of the Binnenthal in Switzerland. The bright yellow streak is sometimes deeper in colour than the crystals themselves; this is strikingly shown by perfectly colourless and transparent crysta's of marshite, which also give a bright yellow streak. Exposure the crystals. The silver is in part replaced by copper, and as to bright sunlight for several days does not affect the colour of this increases in amount, there is a gradual passage from miersite to marshite: "cuproiodargyrite" (AgI.Cul) from Chili is possibly an intermediate member of this group.

The new mineral has been named in honour of Mr. H. A. Miers, F.R.S., Professor of Mineralogy at Oxford, who first correctly determined the crystalline form of marshite, a mineral so closely resembling miersite in appearance that the two species are only to be distinguished by chemical tests. L. J. SPENCER.

UNIVERSITY AND EDUCATIONAL
INTELLIGENCE.

THE Maryland Senate has passed a Bill granting 50,000 dollars a year for two years to the Johns Hopkins University. DR. CHARLES CHREE, Superintendent of Kew Observatory, has received the honorary degree of LL.D. from the University of Aberdeen.

MR. C. B. Rouss, who gave 25,000 dollars for a physical laboratory building in the University of Virginia, has given an additional 10,000 dollars for the same object.

MR. CHESTER W. KINGSLEY, of Cambridge, Mass., has given several large gifts to various benevolent purposes, including the sum of 25,000 dollars each to the Newton Theological Seminary, Andover Academy, and Colby University; the two first named being situated in Massachusetts, and the last in

Maine.

A COURSE of eight Yates lectures in Archæology will be commenced at University College, London, on May 4, by Mr. J. Romilly Allen. The subjects of the first two lectures are the origins of primitive art and the evolution of decorative art, and the general object of the course is to trace the developments of Celtic art.

THE first school of forestry in America has just been created by the legislature of the State of New York, to be connected with Cornell University, and the sum of 10,000 dollars has been granted to cover the expenses of the first year. The school is authorised to purchase forest lands to the extent of 30,000 acres in the Adirondack region.

THE University of Paris has (says the Times) arranged for a loan of 1,700,000 francs from the Crédit Foncier, repayable in 50 annual instalments, for the erection of new buildings in Paris and at Fontainebleau. The Faculty of Science is also about to order the construction at a cost of 25,000 francs of an equatorial, which, after figuring in the Exhibition of 1900, will be placed

in the tower of the new Sorbonne.

Ar the graduation ceremony of the Glasgow University on April 12, the honorary degree of Doctor of Laws (LL.D.) was conferred upon Mr. Alexander Duncan, Secretary and Librarian to the Faculty of Physicians and Surgeons, Glasgow ; Mr. Douglas Dunlop, Secretary-General to the Departmen: of Public Instruction, Cairo, Egypt; Mr. John Inglis, formerly president of the Institution of Engineers and Shipbuilders in Scotland, president-elect of the Institution of Marine Engineers, London; Dr. Elie van Rijckevorsel, of the Batavian Society of Experimental Philosophy, Rotterdam; and Prof. J. M. Thomson, F.R.S., professor of Chemistry in King's College, London.

THE excursions of the London Geological Field Class will begin on Saturday, April 23, with a visit to Dorking, Box Hill,

and Betchworth; and between that date and the middle of July the country from Aylesbury to Cuckfield will be systematically examined by the class so as to draw a section over the trough of the Thames basin, and see the deposits to the north and south of London, which underlie the rocks associated with the chalk. The class has been organised and carried on by Prof. H. G. Seeley, F. R.S., for the past twelve years, without difficulty of any kind, and without assistance. It was established as a class to show that systematic instruction in geology could be given in the open country, and the example it affords must tend to bring about more practical teaching in the matter of field-work. When the class began there was very little of such teaching any. where, but the value of individual observation is now accepted as a canon of scientific education, and the success of Prof. Seeley's work should encourage educationists in their endeavour to get the fact-knowledge entirely substituted for the word-knowledge of books.

SOCIETIES AND ACADEMIES

DUBLIN.

Royal Dublin Society, March 16.-Pro1. G. F. Fitzgerald, F.R.S., in the chair.-Prof. J. Joly, F.R.S., and Dr. H. H. Dixon read a paper on the distribution of coccoliths and on some microscopic organisms found in Dublin and Killiney Bays. Coccoliths have been found by the authors on the Irish coast at Sligo, Slyne Head, Dingle, Waterville, and along the coast of south Co. Dublin, and on the south coast of England at Wey. mouth. Samples of water from Loch Inver and Portstuart did not afford any examples. Coccoliths were also found in the mud obtained in the Severn and Liffey beds. In the paper are also described a new marine Difflugia and organisms from Killiney Bay resembling Ehrenberg's Pyxidicula and Xanthidia from the chalk.-A paper by Prof. W. Noel Hartley, F.R.S., and Mr. Hugh Ramage was then read by the former, the subject being a determination of the wave-lengths of the principal lines in the spectrum of gallium, showing their identity with two lines in the solar spectrum. The authors have found gallium to be a very widely distributed element in the earth, and to be present also in meteoric bodies. It became natural to inquire if it is present in the sun. The wave-lengths of the two principal lines have not previously been determined by a grating spectrograph, and the authors availed themselves of the kind offer of Dr. Adeney to allow them to photograph spectra of gallium with the 21 feet radius grating spectrograph in the Physical Laboratory of the Royal University of Ireland. The two principal lines were photographed as bright and reversed lines in arc spectra, and as bright lines in the spark spectrum of a solution of gallium chloride. In these and in the oxyhydrogen spectrum of gallium compounds the less refrangible line is always stronger than the other. The wave-lengths of the two lines, determined by interpolation from adjacent iron lines, are found to be 4172 215 and 4033*125. In Rowland's map of the solar spectrum there are two lines probably identical with these, namely:4172 211. Source: Aluminium. Intensity: 1, 4033 112. Not identified.

[ocr errors]
[ocr errors]

and It is pointed out that gallium is present in every bauxite and shale examined by the authors, and also in metallic aluminium, and no doubt the line 4172 211 in the spectrum of aluminium is really a gallium line. From the very close agreement of the wave-lengths, from the relative intensities of the lines as shown above, and from the evidence of the wide distribution of the element, it seems certain that the two gallium lines are identical with the two lines above mentioned in the solar spectrum, and there are no other lines so close to these. The evidence is discussed at length in the paper, as also is the effect of the presence of elements upon the spectra of other elements.-Prof. J. P. O'Reilly read a paper on the occurrence of anatase and brookite in the quartzites of Shankill, Co. Dublin. He explained that the minerals were found in a mass of yellow earth, met with by the quarrymen in 1888, and had only lately been examined. The peculiarity of the anatase was its approximation in composition to the clay or mineral analysed by Eakins as mentioned by Dana in his "System of Mineralogy," edition of 1892, p. 716, while presenting the crystalline form of anatase, thus allowing of the presumption that the clay analysed by Eakins and called by him "Xanthitane," was probably the product of decomposition of an anatase having much the same composition as the mineral found at Shankill.

[blocks in formation]

where e is the energy, m the motivity, the temperature of any part of the system, T the lowest temperature in the system, g any coordinate, P the corresponding force, and N, M specific heats. The usual equations are at once deduced by treating de, dm as complete differentials.-Dr. Galt, of Glasgow University, communicated a paper on the microscopical appearances of the grains in the more commonly occurring starches. The paper was full of detail, and was illustrated by numerous original photographs and lantern slides. In a paper on methods of mapping rainfall, Mr. A. J. Herbertson described a simple graphical method for taking into account the varying lengths of periods of observation of rainfall at different parts of the globe. The mean rainfall values were inserted on the maps in different coloured inks, according to the length of period of observation. The general trend of the isohyets could be attained by comparing similarly coloured means, and the final positions of the lines fixed by the values at the stations with the most extended records. The variableness in the length of the month is allowed for by drawing isohyetal lines, whose actual values are the nominal values multiplied by the days in the corresponding month, and divided by one-twelfth of a year expressed in days. In a second paper, on the normal rainfall of India and the abnormalities in 1896, Mr. Herbertson showed maps on the mean annual and monthly rainfall of India, based on the means published in the rainfall data for 1895, and those in the annual summary for 1896.

Royal Physical Society, March 16.-Mr. B. N. Peach, President, in the chair.-Papers were read by Mr. W. S. Bruce, of the Jackson Harmsworth expedition, and Mr. William Eagle Clark, on the mammals and birds of Franz Josef Land. Mr. Bruce, who spent fifteen months on Franz Josef Land in 1896-97, explained that the number of species, exclusive of mammals and birds, he then obtained exceeded that of any previous Arctic expedition, he having secured 236 against 216 to the credit of the United States expedition of 1881-83. He had at least doubled the number of species known to Franz Josef Land. He had found ancient reindeer horns, though there were no reindeer at present in the Land. Among the specimens he exhibited were the bones of whales and walruses found on raised beaches with an elevation

of from 50 to 80 feet, plainly indicating their great age; while one specimen-the scapula of a walrus-was found at a height of 336 feet. The chief point of interest in Mr. Clark's part of the subject, which was restricted to birds, was the finding of several new species-Bonaparte's sandpiper, purple sandpiper, and the shore lark. The first mentioned of these, Mr. Clark said, was not only a new and remarkable addition to the ornis of Franz Josef Land, but it was the first authentic example of this American species that had been obtained in Europe elsewhere than in the British Isles. Another subject of interest in the paper was the description of a newly-found nesting-place of the ivory gull. This was at Cape Mary Harmsworth, on what was considered to be one of the largest pieces of bare ground in Franz Josef Land. Of the twenty-two species of birds which formed the avifauna of Franz Josef Land, only ten had been found breeding, though several more undoubtedly nested there, while several, again, were mere stragglers.

[blocks in formation]

water, and has studied in detail the alterations in structure and movement brought about by the new conditions of life.-On the deformation of compressed parts and the stability of large frame-works, by M. A. Bérard.-On congruences which are in several ways K congruences, by M. C. Guichard.-New expression of the elements of an orthogonal system by theta functions of two arguments and their application in dynamics, by M. E. Jahnke.-On a transformation of Hamilton's equation, by MM. W. Ebert and J. Perchot. -On the deformations experienced by a solid dielectric on becoming the seat of an electric field, by M. Paul Sacerdote. The phenomena in question are shown to be deducible from the principles of the conservation of energy and of electricity.-On a problem in the analytical theory of heat, by M. W. Stekloff.-On the electric conductivity of solutions of permanganate of potassium, by M. Emmanuel Legrand. The molecular conductivity increases with the dilution, and approaches the limiting value 124 obtained by former experimenters for neutral salts at 25° C.-On multiple resonance, by M. Louis Décombe.-On the thermic mercurial ampère-meter and its industrial applications: new standard of electromotive force, by M. Charles Camichel. — Comparison of the atomic weights of hydrogen, nitrogen, and carbon deduced from physical data with their values as deduced from chemical analysis, by M. Daniel Berthelot. The author claims that the calculation of atomic volumes and atomic weights from accurate determinations of the density and compressibility allows of the confirmation and, in certain cases, of the statement with precision of the results given by chemical analysis. The results obtained by various observers in the case of the three elements mentioned are criticised in detail. -Isoquinoline and tetrahydroisoquinoline, by M. Marcel Delépine. A thermo-chemical study.-On the estimation of small quantities of carbon monoxide in air and in normal blood, by M. L. de Saint-Martin. The author, in reply to the criticisms of M. Gautier, further explains the analytical modifications introduced by him. A series of experiments are described to demonstrate the presence of carbon monoxide in the blood of animals living in large towns. On the spectrum and the nature of neodymium, by M. Eug. Demarçay.-Action of oxidising agents on some nitrogenous bodies, by M. Echsner de Coninck. An account of the action of hypochlorites, in presence of excess of alkali, upon amines, diamines, hydrazines, cyanic and cyanuric acids, and various alkaloids.-Combination of mercuric nitrate and trimethyl carbinol, by M. G. Denigès. The author describes the preparation and properties of a new compound, which he terms mercuroso-mercuric dimethylethylenic nitrate.-On the physiology of gentianose; its hydrolysis by soluble ferments.Detection of wood saw-dust in flour, by M. G. A. Le Roy. The suspected sample is gently warmed with an alcoholic solu tion of phloroglucinol, strongly acidified with phosphoric acid. The particles of saw-dust are stained an intense carmine-red colour, while the starch and cellulose of the grain itself are little, or but slightly, affected.-On the crystalline forms of the oligist of Puy de la Tache (Mount Dore), by M. F. Gonnard.On the micro-organisms of "turned" wines, by MM. F. Bordas, Joulin, and de Raczkowski. The authors have isolated and studied an organism, which they propose to term Bacillus roseus vini from the colour assumed by its cultivations in certain media.-Effects of the solar and lunar attractions upon the atmosphere of the northern hemisphere at each of the four phases, by M. A. Poincaré.

[blocks in formation]

ZOOLOGICAL SOCIETY, at 8.30.-On the Breeding of the Dragonet (Callionymus lyra): Ernest W. L. Holt.-On the Serricorn Coleoptera of St. Vincent, Grenada, and the Grenadines, with Descriptions of New Species: Rev. H. S. Gorham.-Note on the Affinities of Palæospondylus gunni, Traq.: Dr. Bashford Dean.

INSTITUTION OF CIVIL ENGINEERS, at 8.-Paper to be discussed: The Electricity Supply of London: A. H. Preece.

ROYAL VICTORIA HALL, at 8.30.-X-Rays: Bruce H. Wade.

WEDNESDAY, APRIL 20.

SOCIETY OF ARTS, at 8.-Stage Mechanism: Edwin O. Sachs.
GEOLOGICAL SOCIETY, at 8.-Note on an Ebbing and Flowing Well
Newton Nottage, in Glamorganshire: H. G. Madan.-Petalocrinut E
A. Bather. On the Origin of the Auriferous Conglomerates of the God
Coast Colony (West Africa): T. B. F. Sam.
ROYAL METEOROLOGICAL SOCIETY,at 7.30.-Anticy clonic Systems and their
Movements: Major H. E. Rawson.-Results of Observations on Hat
and Transparency in 1897: Hon. F. A. Rollo Russell.
ROYAL MICROSCOPICAL SOCIETY, at 7.30.-An Exhibition of Diatoms:
H. Morland. At 8.-On some Organic Substances of High Refractivity
available for Mounting Specimens for Examination under the Microscope.
H. G. Madan.-Instantaneous Photomicrography: E. B. Stringer.
THURSDAY, APRIL 21.

SOCIETY OF ARTS (Indian Section), at 8.-Recent Railway Policy in India:
Horace Bell.

[blocks in formation]

BOOKS, PAMPHLETS, and SERIALS RECEIVED. BOOKS.-The Barometrical Determination of Heights: F. J. B. Cordeir (Spon) -A Manual of General Pathology for Students and Practitioners: Dr. W. S. Lazarus-Barlow (Churchill). - Practical Radiography: A. W Isenthal and H. S. Ward, 2nd edition (Dawbarn).-Elementary Chemistry. T. A. Cheetham (Blackie).-Synopsis Characearum Europaearum : Dr. W Migula (Leipzig, Kummer).-Accounts of the Trade carried by Rall and River in India in the Official Year 1896-97 and the Four preceding Years (Calcutta).-Notes on Observations: S. Lupton (Macmillan).-An Ele mentary Course of Physics: edited by Rev. J. C. P. Aldous (Macmillan) — Essays on Museums, &c.: Sir W. H. Flower (Macmillan).

PAMPHLETS.-Some New Indo-Malayan Orchids: G. King and R. Pantling (Calcutta).-A Simple Guide to the Choice of a Photographi Lens: T. R. Dallmeyer (J. H. Dallmeyer).

SERIALS.-Knowledge, April (High Holborn).-Bulletin of the Americas Mathematical Society, March (N.Y., Macmillan).-Transactions of the Astronomical and Physical Society of Toronto, 1897 (Toronto). -Obser atory, April (Taylor).-Atlantic Monthly, April (Gay).-Journal of the Sanitary Institute, April (Stanford).-Zeitschrift für Wissenschaftliche Zoologie, lxiii. Band, 3 Heft (Leipzig, Engelmann).—Materials for a Fl of the Malayan Peninsula: Sir G. King, No. 10 (Calcutta).-History of Mankind: F. Ratzel, translated, Part 25 (Macmillan). - Psychologica Review, Monograph Supplements, Vol. 2, No. 2 (Macmillan)-Reliquary and Illustrated Archæologist, April (Bemrose).-Mind, April (Williams).

[merged small][ocr errors][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][merged small][ocr errors][merged small][merged small][merged small][merged small]

Scientific Experts and Patent Cases

Photographic Surveying

Balnibarbian Glumtrap Rhyme. By Prof. G. M.

Minchín, F.R.S.

Notes. (Illustrated.).

Our Astronomical Column:

The Doubling of the Canals on Mars.

Comet Perrine

The April Lyrids

The Meudon Observatory

Prehistoric Ruins of Honduras and Yucatan, ('strated.) By Alfred P. Maudslay

Recent Papers on Glaciation. By G. W. L. Miersite, a Cubic Modification of Native Silver Iodide. By L. J. Spencer.

University and Educational Intelligence i

Societies and Academies

Diary of Societies

Books, Pamphlets, and Serials Received

[ocr errors]

500

500

561

501

561

562

503

564

[ocr errors]

568

508

569

500

57

574

574

575

MAY 16 1899

THURSDAY, APRIL 21, 1898.

A NEW DEPARTURE BY THE RAY

SOCIETY.

The Tailless Batrachians of Europe.

Part i. By G. A. Boulenger, F.R.S. Pp. 210. (London: The Ray Society, 1897.)

THE

In

HE publication of this elegant treatise marks an event in the history of the Ray Society upon which its members, so long content with a diet of insects, are to be heartily congratulated. Of the 210 pages of the work, 121 are devoted to an "Introduction" in which the classification, taxonomic characters, skeleton, viscera, habits, and reproduction of the Batrachia Ecaudata are successively dealt with on broad lines, special sections being added on hybrids and geographical distribution. The remaining ninety pages are devoted to a systematic treatment of the Discoglossidae and Pelobatidæ (¿.e. of eight of the twenty European species which the author admits), in which specific diagnoses, geographical varieties, the skeleton, habits, eggs, tadpole, and habitat, are categorically dealt with in popular but trustworthy terms. This arrangement has involved the author in an amount of repetition, but owing to the judicious placing of the seventy-seven processed drawings which adorn the work, all suspicion that this may be needless disappears, text and illustrations being found to supplement each other in accordance with a well-conceived plan. addition, there are two maps and ten plates, six of the latter being admirable examples of the chromo-lithographer's art, of which it is praise sufficient that the author declares them to have fully satisfied his aspirations. The classification adopted is that of Cope, as emended by the author in the course of five-and-twenty years' experience, its leading feature being the grouping together of the genera Alytes, Bombinator, and Discoglossus, as a family (the Discoglossidae) having well-defined and lowly affinities, which all recent investigation has confirmed. Mr. Boulenger is the foremost among the world's younger herpetologists, and in knowledge of his experience acquired during the custody of the world's greatest collection of reptiles and batrachians, of his devotion to his calling, and of his well-tried judgment, expectation ran high on the announcement of the work. It has been realised; suffice it to say that the book marks an epoch in the popularisation of zoological science, and must take its place in history beside the memorable works of Rösel von Rosenhof and Spallanzani, "Die in Deutschland lebenden Saurier" of Leydig, and others of the kind. It abounds in original observation and teems with enthusiasm, and without it no zoological library worthy the name can be complete.

The section dealing with the viscera is somewhat less satisfactory than the rest, but it is fair to the author to remark that he purposely excludes a general description of the "internal soft anatomy," and confines his attention to the "structure of the lungs and urogenital apparatus," which he regards as "of special importance from the point of view of the systematist." He in this way leads up to his morphological tour de force, in which (Sections

9 and 12 more particularly) he deals in an altogether masterly manner with the breeding habits and metamorphosis, earlier published papers upon which have rendered him famous. And in this connection it is particularly noteworthy that an observer of such ripe experience should pronounce against the popular ideas concerning the significance of the tadpole stage. Believing, as we do, that the conception of the trog's climbing up its own phylogenetic tree is erroneous, and that in the recognition of characters expressed in the term "derotrematous," in respect to which condition some living Batrachia are veritable fishes, far-reaching generalisations founded on the piscine resemblances of the tadpole are superfluous and have been misleading, we hail with ¦ much satisfaction the author's assertion that "larval forms such as the tadpoles are outside the cycle of recapitulation."

The only call for revision which we note is in the terminology, and that more particularly anatomical The usage of the terms "epicoracoid" and "sternum" is regrettable, since the former, as an independent element of the shoulder-girdle, has no existence in the Batrachia, and in them the latter is known to be no derivative of the costal skeleton. "Abdominal cavity' is equally inexpressive, and the application to the vertebræ of the term "dorsal" (still so barbarously retained for the thoracic of the amniota) is wrong. The description of the os cruris on one page as the crus or tibia" and on another as the " tibia-fibula," like that of the investment of the ovum as a "gelatinous envelope" and a "sticky mucilage," is contradictory; while the reference. to the fronto-parietals of Pelobates, on p. 35, is incomplete, by lack of insertion after "in" of the words "the adult." Articulary balls" is amusing in its unconventionality, and “adhesive sub-buccal apparatus" is needlessly involved. The description of the so-called external type of vocal-sac as occurring in Rana, involving “a diverticulum of the mylo-hyoid muscle" and the said "slits at the sides of the throat," is calculated to convey a wrong impression of the facts, and error appears most seriously to have crept into the account given of the genital ducts of the males, in a manner alluded to below, for which it will be seen the author is little to blame.

[ocr errors]

The above-named are but trivial defects and unfortunate modes of expression, which in no way detract from the merits of the book. The author in his preface deplores the fact that few persons share with him a fondness for the Batrachia Ecaudata, and it must be admitted that, with the Teleostean Fishes and other groups of animals forming culminating series in definite lines of modification, these have been largely neglected by recent investigators, 'who, fascinated by the lowly and more generalised, have put them aside as useless in their specialisation. The study of the Teleostei is now setting these persons right on fundamentally important topics, and we claim that the remarks appended to this review justify the assertion that in the study of the despised Anura there lies the settlement of that which is to-day one of the most vexed questions concerning the genital ducts of the vertebrata. And tempted thus to speculate

1 "Presacral" is the only term by which these can be accurately described in the Batrachia.

upon what remains to be ascertained about mere frogs and toads, the mind reverts to their mechanism of accommodation for vision within and without the water, our knowledge concerning which is an absolute blank. If we may judge by analogy to the inanimate, displacement of the lens of an altogether remarkable order must take place, and there is thus opened up a line of investigation of absorbing interest alike in its morphological, physiological, and physical aspects, in which, to say the least, there probably lies the explanation of the

remarkable series of accessory eye-muscles which these animals possess.

That a great deal remains to be done in the study of these familiar creatures is certain. The author has

produced a masterly treatise upon their classification and distribution, upon which he is now a leading authority. He deals with a subject historically associated in a prominent manner with the labours of English-speaking zoologists, and tells us that he will be content if those who use the book may derive from the perusal of its pages one-tenth of the pleasure it has given him to write them. His preface, in which this sentiment occurs, is positively infectious in its enthusiasm, force of personal example, and love of science for its own sake; and neither he nor we could desire more of his book than that it might stimulate to action some one who should in turn succeed him as a foremost authority upon the group

of animals with which it deals.

[ocr errors]

Concerning the vestigial portions of the urinogenital apparatus above referred to, the author, relying only upon macroscopic characters and following Spengel, has described the duct which in Alytes receives the vasa efferentia as Müllerian; and he regards the vesicula seminalis in all forms as a derivative of that. He omits mention, however, of the vestigial Müllerian duct of the male Rana, which, though exceedingly delicate, is usually present; and this is the more regrettable, since Marshall proved microscopically that it skirts the outer border of the vesicula as an independent tube. The relationships of the vesicula to the so-called "ureter" in Rana, and to the presumed Müllerian duct in Alytes, the alleged homology of which has been challenged, are thus seen to be identical, wherefore the latter would appear to represent the Wolffian duct proper, and the so-called " ureter of the Anura either a specialised portion of that, or an independent duct arising from the kidney, as might well be from the condition in Alytes and some Urodela. Comparative embryologists will not need to be reminded that a precisely similar difficulty besets the interpretation of the corresponding parts in the Elasmobranch fishes, and as concerning the Anura more particularly the whole matter, anomalous to an unparalleled degree on the Spengelian interpretation, apparently harmonious and exceptionally instructive by extension of Marshall's observation, demands renewed microscopic inquiry. Indeed, to the present writer it has long appeared that the male genitalia of Alytes and Discoglossus, as here interpreted, conform to a type transitional between that of the Urodela in which a fully developed Wolffian body, differentiated into a sexual and a renal portion, is present, and of the higher Anura, in which the homologue of the renal part receives the vasa efferentia, and to

[blocks in formation]

J. de Morgan. Avec la collaboration de MM. Wiedemann, Jéquier, et Fouquet. Pp. x + 395. (Paris: Leroux, 1897.)

THE HE large section of the scientific public which is interested in prehistoric remains will, we are sure, cordially welcome the second part of M. de Morgan's work on "Les Origines de l'Égypte," which is now before us. Every reader of the first part waited, we fear with some impatience, for the supplementary facts which were known to be forthcoming; and now that they are in our hands, it is more possible to judge of the general effect of M. de Morgan's recent discoveries upon the sciences of archæology and anthropology. For some years past the natives of Upper Egypt have been offering numbers of curious objects for purchase to the tourist and wandering Egyptologist, and the said objects were so remarkable from artistic and other points of view, that more than one archæologist have pronounced them to be forgeries. That these objects came from several different places in Upper Egypt was quite certain, but it was hard to believe the fact, and most people, whatever they said, privately thought the statements of the natives to be unbelievable.

M. de Morgan was the first to find the solution of the difficulty, and now he has triumphantly proved that these strange objects do really come from a number of sites which extend along the Nile Valley from Cairo on the north to Wady Halfa on the south, and that they represent the remains of a people who occupied Egypt before the Egyptians who have hitherto been known to us from inscribed statues, temples, &c. In the second chapter of the present volume of his work he gives a list of these sites, and it may be considered the most important section of his book; it is much to be hoped that now circumstances have obliged him to transfer the field of his labours to Persia, others, whether they be English or French, may take steps to examine by means of systematic excavations the sites of which he has given us such a full list.

But though M. de Morgan has not been alone in making researches concerning the history of the remote period in which these sites were occupied, and though Messrs. Petrie and Amélineau have collected much information from their excavations at Amrah, Ballas, and Nakada, it must not for one moment be imagined that all the questions connected with the prehistoric people of Egypt can be answered, or all difficulties solved. Nor can it be said whence this people came, or when they first occupied their stations in the Nile Valley; at present it is difficult even to find a name for them which will satisfy both M. de Morgan and Mr. Petrie. M. de Morgan, basing his opinion upon anthropological evidence

« PreviousContinue »