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those termed English include several varieties of foreign platinum foil, they burn away, leaving no residue. The origin which are commonly grown in England. In most quantities at present available are too small for the ready cases the trees were on the crabstock :

determination of density or hardness.

Negative results were invariably obtained in control ex117 English

May 6.4

periments on the commercial calcium carbide which was 36 Scotch

May 8.9

used in preparing the alloys. 9 Irish

... May 9:4

Tin may be used in place of lead, but it is freely oxidised 8 French ... ...

... May 9.0

by the steam, and the resulting dioxide is troublesome to (1 German

... May 4.0)

get rid of. Of other reactions which appear to have 7 Russian ...

... May 8.6

yielded minute crystals of diamond, the following may be Another point of some interest in connection with these mentioned :—boiling benzene or toluene in contact with results may be mentioned, namely, that there is a con

finely powdered potassium dichromate or with concentrated nection between the earliness of blossoming and the earli

aqueous solution of gold chloride; heating benzene or

toluene mixed with carbon tetrachloride or chloroform to ness of the ripening of the fruit, though it is so slight that it becomes apparent only when the averages of a

200° C. to 300° C. in a bomb. In the last named reconsiderable number of varieties are taken, and many

actions, nearly all the carbon separates out in the individual instances may be noticed where the later fruit

amorphous form, hydrochloric acid collecting under follows the earlier blossoming :

enormous pressure.

I hope shortly to return to the subject of these experi37 Early varieties ... ... ... May 4.7 ments, and to make a fitting acknowledgment of my deep 40 Mid-season varieties ... ...

... May 6.3

indebtedness to Mr. W. J. Hartley, to Messrs. Neville and 40 Late varieties ... ... May 8.0 | Hercock, and to other friends.

C. V. BURTON.

4 Chesterton Hall Crescent, Cambridge, August 19. This letter, I fear, is already too long, but it leaves unmentioned several points which may be of importance in determining the fruiting of trees. SPENCER PICKERING.

The Spread of Injurious Insects.
Is 1898 Dr. L. O. Howard forwarded to me a scale

insect discovered by Prof. Chaves at Ponta Delgada, Artificial Diamonds.

Azores, attacking the foliage of the orange tree. The Of the two phases, diamond and graphite, diamond is

insect proved to be new, and was described as Lecanium the denser, and has also the less internal energy. It

perlatum. Since that time it has never been reported from follows that, if carbon can be crystallised at comparatively

any other place; but now I have received some large, low temperatures, the minimum pressure sufficing to de

flat, dark brown scales on orange leaves from Villa termine the diamond form will be lower than that

Encarnacion, Paraguay, collected by Mr. Schrottky, and employed in M. Moissan's experiments.

they are this very same L. perlatum.' This is only one For estimating the transformation temperature corre

new case to be added to the many already known of scale sponding to low pressures, the data available are incom

insects being transported from one side of the world to plete; it is here suggested, however, as a tentative result

the other, evidently by human means. It is to be regretted from experiments which are still in a preliminary stage,

that the British Government, with its numerous tropical that the transformation temperature corresponding to colonies and excellent botanical gardens, has not done atmospheric pressure lies somewhere between 550° C. and

something to make known the scale insects within its 700° C., or not far outside those limits, temperatures

domains. It is true that Mr. E. E. Green, the Governhaving so far been judged only by eye.

ment entomologist of Ceylon, is bringing out a magnificent A molten alloy of lead with about i per cent. calcium

work on the scale insects of that island ; but he finds inappears to be capable of holding in solution some small sufficient support, and it is divulging no secret to say proportion of carbon, which exists either as free carbon

that the publication of this useful book will involve him or as calcium carbide ;

in very serious financial loss. There is no properly and if the calcium is

classified national collection of scale insects (the only good eliminated from the molten

collection in England is that of Mr. Newstead at Livermass, some carbon

pool), and we are still totally ignorant of the coccid fauna crystallises out. Steam,

of many colonies. The reasons for regretting this confor example, converts the

dition of affairs are mainly two :--(1) because in ignorance calcium into hydrate with

pests of this group are continually being carried to new out attacking the lead.

regions, where they are liable to become destructive ; and If the reaction has

(2) because man is so mixing up the distribution of these occurred at a full red heat, insects that every year makes it more difficult to ascertain graphite is found in the

their natural habitats. Having regard for the experiences crust of lime; if only a

of the past, it is surely safe to say that the annual very low red heat has

expenditure of a few hundred pounds in the investigation buen attained, no graphite of these pests would be far more than repaid in economic is found, but a number of as well as scientific gains.

T. D. A. COCKERELL. very small or microscopic l'niversity of Colorado, U.S.A., August 10.

crystals, which have many Fig. 1.-Supposed diamond from lead of the properties of the calcium-carbon solution. diamond. The illustration

A Parasite of the House-fly. is from a pencil drawing

I SHOULD like to direct attention to an interesting of a very minute crystal, viewed under a magnification

| parasite of the house-fly which is in this district extremely of 8o diameters, and drawn on a greatly enlarged scale.

abundant this summer. The creature is, as a rule, very The crystals obtained exhibit mostly faces of the octa

hard to find, and many thousands of flies may be caught hedron, modified by the cube and dodecahedron; in no case

in ordinary seasons without a single parasite being found has any internal flaw or lack of perfect transparency been

upon them. The animal in question is one of the Pseudodetected in them. The refractive index is clearly very

Scorpionides (? Chelifer), easily recognisable by its pair high, and an attempt to determine it by displacement of of the

of long chela, and I should be glad if any of your readers focus gave 2.43 (instead of 2.47), any convexity of the

I would inform me to what genus it belongs and whether refracting surface tending to give too low a value. The

it is equally abundant this year in other places. crystalline faces are, in fact, generally if not always

1 Eton, August 19.

M. D. HILL. convex, in many cases strongly so. The crystals adhere tenaciously to clean dry glass: they are unacted upon by; In my original descriprion, it is stated that the skin is not reticulated. ordinary acids (hot or cold), by cold hydrofluoric acid, and

i The new material shows that it is minutely reticulated or tessellate in the

I middle of the back. The antennae, described as jointed, vary to 7.jointed, by fused alkali at a red heat. When strongly heated on with the fourth joint longest, but the third nearly as long.

LE

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found in Scandinavia, Germany, France, and even JORE LIGHT ON ANCIENT BRITAIN."

the Troad. IT is gratifying, and at the same time puzzling, to The intricacies of the text are considerably simpliI find that the antiquities discovered in part of fied by numerous diagrams, giving the plan and a single county can provide material for two such vertical section of the barrow under examination, voluminous works as Canon Greenwell's “British and a specimen is here reproduced to show how it is Barrow's ” of 1877 and the record of Mr. Mortimer's possible to read the history of a burial mound. One researches, now issued with the assistance of Mr. in the Aldro group measuring 84 feet in diameter Sheppard, the energetic curator of the Hull and 5 feet in height was excavated in 1866. The Municipal Museum. The district investigated lies clay and soil forming the between York and Bridlington, and teems with relics | upper part is marked A. of the past, most of the barrows, or burial mounds, while B is a boat-shaped dating from the Bronze Ige, but two or three mass of clay and soil below cemeteries containing Anglo-Saxon graves at least a it, c being the chalk filling thousand years later. The excavations in which the of the inner mound and author has been concerned for so many years are | grave below the original well described; but those without special knowledge surface-level Ew. Nos. 1-8 of the period will turn with most satisfaction to the are interments of children introduction, where, with the aid of copious extracts and adults in a pit cut rather from the earlier work already mentioned, some in deeper than usual in the teresting generalisations are made from the data fur chalk rock; but they were nished by the spade. Evidence is brought forward not all complete skeletons, in favour of cannibalism among the ancient Britons, No. 7, for instance, being a a practice that has been suspected for some time; heap containing a "drinkand human sacrifice, perhaps also suttee, seems to

ing-cup " in 48 pieces, fraghave been indulged in at the burial of an important ments of six human lowerpersonage. In some barrow's there were signs that jaws, and a number of smail a circular hut or a pit-dwelling had been used as a

bones packed in an adult sepulchre, the walls and roof being thrown down calvarium. Whether conover the body; and the author's suggestion as to the

temporary or not, these
burials had been surmounted
by a dome of chalk which
was cut into for another
burial at some later date
and subsequently covered
with the outer mound.

Of the succeeding Early
Age of iron remains are few

in this particular district,
Fotopabetodos though abundant a few

miles further north; but one
burial of importance must be

noted. The swords here
Fig. 1.-Section of Round Barrow, Aldro, E.R. Yorks.

illustrated were found with
a skeleton, and belong to

two distincttypes; the origin of the incomplete ring formed by stones or

longer is of usual dimen

lone a trench round many burials of the period is cer

sions and has the charactertainly plausible. In his own words, “ these rings are

istic curved scabbard-mouth probably marks of taboo or enclosures which were

and the chape of the middle made at the beginning of the ceremony to mark off

period of La Tène, while the and protect the sacred spot in which the ceremony

shorter sword is the only and interment were afterwards to be conducted, and

one of the kind known to the break in the circle had no other significance than

have been found in this to serve as a place of ingress and egress during the country, and with similar performance of the obsequies."

examples from France and It is interesting to have existing evidence as to

Switzerland may date from the sepulchral pottery confirmed by further dis- | about 100 B.C. 'The human coveries. With a few very doubtful exceptions the head between the branches so-called “ drinking-cup" is never found with cal- of the pommel is evolved cined human bones, and generally accompanies the from the knob that appears primary, or at least one of the earliest burials, in in that position on certain the mound or the grave beneath it. Of the “ food short swords from the Hall

FIG. 2.-Early Br tish Suonis, vessels,” 43 were found with cremations and 119 with statt cemetery.

&c., North Grimston, ER unburnt skeletons; and these figures agree with The Anglo-Saxon ceme

Yorks. Canon Greenwell's, giving a proportion of about teries contain unburnt one to three. Though occasionally found on the top bodies of which the orientation is instructive, while of calcined bones, the cinerary urns, as their name many excellent brooches and other relics have been implies, were generally used to contain the ashes of recovered. These and the vast Bronze Age series the dead, and “incense-cups" are invariably asso have been amply and creditably illustrated, but, unciated with the rite of cremation, though we must gallant as it may appear, a protest must be lodged contest the statement that the latter vessels are also against the frontispiece, which gives a totally false 1 "Forty Years' Researches in British and Saxon Burial Mounds of East

impression of the Grimthorpe sword. In a work Yorkshire." By J. R. Mortimer. Illustrated by Agnes Mortimer. Pp.

containing so many references misprints are excus1xxxvi + 452. (Hull: A. Brown and Sons, Ltd., 1905.)

able, but some are irritating; thus, Inverary (p. 361)

Hotdooooo

should be Inverury, and the next page has a cruel If Mercury has an atmosphere, the horns of the mutilation of Le Gros Guignon, while the reference crescent should appear prolonged by atmospheric re10 Archaeological Journal on the page before should fraction, and a careful observer, suitably equipped, be to the York volume (1848).

| should be able to detect the prolongation, and possibly Following an excellent example, Mr. Mortimer to observe the spectrum of the tips. furnishes relic-tables with all necessary details at the M. Touchet suggests that the moon might be end of the volume, together with a copious index. | observed, both before the first and after the fourth Comparison with Canon Greenwell's table shows a contacts, projected on the brighter portions of the very large proportion of primary interments, there lower corona, by an observer employing a suitable being in one case as many as seventeen, to three dark glass with a small telescope. secondary; but in a matter of this kind different 1 In a brochure recently received from Señor Horacio conclusions might be drawn from the same data. Bentabol, of Madrid, the author makes a number of Altogether the work is most welcome as a fund of suggestions to eclipse observers by which the existmaterial for more general treatment, and should ence of a lunar atmosphere might be detected. encourage the study and publication of prehistoric Among other matters he suggests that delicate finds in England.

thermometric observations made for some hours before and after the eclipse might exhibit a heat-absorption

effect due to the interposition of the lunar atmoTHE FORTHCOMING TOTAL SOLAR sphere, between the sun and the observer, before the ECLIPSE.

actual body of the moon was interposed. Solar radi

ation observations might also exhibit the same effect. RY the time that NATURE appears next week, the

Photometric observations of the illumination of the D total solar eclipse of August 30 will have become

sky might show an analogous absorption of light, an event of the past, and we hope then to be in a

due to the lunar atmosphere. Exact determinations position to announce that the careful preparations,

of the solar diameter would, if the moon possesses which have occupied the minds of astronomers for so

an atmosphere, probably show the results of the remany months past, have been crowned with success.

fraction due to that atmosphere. The apparent Since the appearance of Dr. Lockyer's article con

| hourly movement of the sun should become modified, cerning the eclipse, in our issue of February 23,

| as the lunar atmosphere is interposed, for the same several important modifications in the proposed

reason. Many other points whereby the existence of arrangements have been made, but most of the eclipse

such an atmosphere might be tested are given by observers are now at their stations erecting or adjust

Señor Bentabol. ing their instruments for the final scene on Wednes

As recently mentioned in these columns, French day next. How much depends on the nicety of these

astronomy will be well represented at the various adjustments can only be understood by those in

stations, whilst American astronomers have journeyed timately concerned; but when it is recalled that since

to a number of widely separated stations. Three the general introduction of photographic methods

expeditions have been sent from the Lick Observatory into eclipse work the sun has only been eclipsed for

to Labrador, Spain, and Egypt respectively. At about half an hour, that the duration of totality in the

each station a search is to be made for an intracoming event exceeds 31 minutes, and that no favour

Mercurial planet, and large-scale coronagraphs of able opportunity will occur again until 1912, when

exactly similar construction are to be employed. totality will only last for about 60 seconds, some idea

Should any actual movements take place in the corona may be obtained of the anxiety of those observers

during the two and a half hours which elapse between who are fortunate enough to take an active part in

totality at Labrador and at Assouan, the photographs next Wednesday's observations.

obtained at these respective stations should show it. Subjoined to this article is a letter from Dr.

The Canadian Government has dispatched an W. J. S. Lockyer describing the preliminary oper

expedition to Labrador, and has officially invited ations of the eclipse expedition of the Solar Physics

Mr. and Mrs. E. W. Maunder to accompany the Observatory, under the personal direction of Sir

same. Mrs. Maunder will employ a coronagraph Norman Lockyer, K.C.B. When all arrangements

| exactly similar to that which Prof. Turner is using for this expedition were nearly completed, but before

in Egypt. Sir Norman Lockyer left England, it was decided

The details concerning the regions crossed by the by the French Government, in quite a friendly spirit,

eclipse track, and the times of totality, &c., have that the presence of a foreign inan-of-war in Philippe

already been given in many places, but the subjoined ville harbour was not desirable at the present time;

table giving the times and magnitude of the greatest therefore arrangements were made with the Spanish

phase in these islands may be of interest :authorities, who rendered such valuable help to the similar expedition in

Eclipse begins Greatest eclipse Eclipse ends Mag. 1900, for the party to go to Palma. Some of the work contemplated at Palma Green'vich 29 23 49 ... 30 I 4 ... 30 2 15 ... 0786 is described by Dr. Lockyer in his letter.

Edinburgh 29 23 44 ... 30 o 55 ... 30 2 4 ... 0*724 Some novel observations will be made by other Dublin ... 29 23 39 ... 30 O 53 ... 30 2 5 ... 0*799 observers. In a recent communication to the British Astronomical Association Mr. C. E. Stromeyer

In the above table, which is taken from the Compointed out that geodesy might be assisted by an

panion to the Observatory, the times are Greenwich accurate determination of the

the previous path

Mean Time, which is reckoned from

of totality. This path has been computed on the assumption

mean noon, and the magnitude is given with the that the earth has a certain form, and if the

sun's whole diameter as unity. computed values are found to be incorrect, the errors in the assumption might be discovered.

The Solar Physics Observatory Eclipse Expedition. Another valuable suggestion was made in a letter

Palma, August 18. from Dr. Johnstone Stoney which appeared in these We have now been at Palma a week to-day, and columns on July 13, wherein the writer pointed out ! are all thoroughly settled down, not only at the that the planet Mercury will be very near to a line ! very excellent hotel in which we are located, but at joining the earth and the sun, and will therefore the eclipse camp, which lies about a mile towards present a very thin crescent to the observer's view. / the north-west. We are a large party. There are

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150 volunteers from H.M.S. Venus, including the The erection of the piers for the instruments comcaptain and all the officers, and we ourselves total menced on the following day, and so soon as these six, namely, Sir Norman Lockyer, Mr. C. P. were completed the instruments which were to be Butler and myself, and three volunteer observers, placed on them were put together and set up. Lady Lockyer, Mr. Howard Payn, and Mr. Frank At the time of writing (August 18, 10 p.m.) great McClean.

progress has been made; most of the instruments are We arrived here on the morning of August 10, | nearly erected, some are in approximate adjustment, having transhipped at Gibraltar to H.M.S. Venus while they are now all under canvas, the coverings about noon on August 8. The arrangements for having been set up in truly nautical style. transferring the 110 packing cases from ship to ship To gain some idea of the work undertaken, it may were all that could be desired, an Admiralty lighter be mentioned that the larger instruments include a and tug being in readiness on our arrival. By five prismatic reflector of 76 feet focal length, a 6-inch o'clock in the afternoon we were steaming away three-prism prismatic camera, two coronagraphs (one towards our destination, leaving behind us that great 16 feet focal length) and an objective grating camera pile of rock, which eventually became a dim speck worked in connection with one cælostat, a triple on the horizon.

camera of 3-inch aperture and 12 feet focal length Needless to say, the conversations in the captain's for photographing the eclipsed sun in colours, and a cabin, in the wardroom, and in many other parts of 37-inch coronagraph worked equatorially. Already the ship were concentrated on eclipse matters, and each instrument has a party from the ship to assisi this culminated in a lecture which I was requested to in working it efficiently, and these are daily in the give to the whole available ship's company. The camp to render aid when necessary. keenness displayed was universal, and the following In addition to the above-mentioned assistants for day volunteers were called for to assist in the work the instruments, there are several other pieces of for the eclipse, and, as I have previously mentioned, work which are being taken in hand. Thus the disc they now total 150. The same evening Sir Norman | party has already erected discs of various sizes on Lockyer gave a lecture, which increased, if possible, imposing structures on the east side of the ground. the keenness previously displayed.

Further, there are groups of observers for sketching On our arrival at Palma, which, by the way, is the corona without discs, making star observations, situated in a beautiful bay with an excellent recording the colours of the corona and landscape, anchorage, the ship was boarded by numerous officials observing the shadow-bands and sweep of the shadow, after the customary salutes had been exchanged making ineteorological observations, &c. between the ship and the fort. Amongst those who These and other parties are daily being drilled to came on board was our friend Mr. Howard Payn, render them as efficient as possible, and there is every who had preceded us in order to fix on a suitable hope that eclipse day will find them skilled and site for our camp, to arrange for local labour and accurate observers. material, and to smooth things generally for us. We are, however, rather doubtful as to the kind of The very admirable way in which this difficult and weather that will be experienced here on the eventful delicate task was accomplished by him in conjunction day. So far, the chances have been in our favour, with Mr. Roberts, the British Consul at Barcelona, / but partially clouded skies are more common than one could not be surpassed, and all the members of the would like to see. A sharp thunderstorm broke over expedition are unanimous in singing their praises. the town on the early morning of August 17, and For the expedition to Spain in 1900 Mr. Payn rain fell in torrents. Fortunately there was no wind, rendered a similar service, and on that occasion the and no damage was done. Those acquainted with arrangements he made were all that could be desired. the local weather conditions cheer us up by forecast

On the afternoon of our arrival at Palma, Sir ing fine weather, but clouds are far more frequent Norman Lockyer and Captain Eyres, in the company than one would wish them, and the prospects are not of the British Vice-Consul, Mr. Bosch, paid some nearly so good as they were in India in 1898 or official visits, and afterwards the site selected by Mr. Spain in 1900. In less than a fortnight's time our Payn was visited. This site is an ideal spot for a | fate will be sealed. large eclipse camp, being sufficiently close to a land- In addition to our party, numerous other observer ing stage for boats, walled in, and perfectly open for of different nationalities are taking or have taken astronomical observations in all directions. The up their stations in the neighbourhood of the town. ground, which is private property, has been kindly

WILLIAM J. S. LOCKYER. lent by the owner for the purposes of the eclipse observations, and the members of the expedition are extremely grateful for the use of such an admirable FIRST INTERNATIONAL CONGRESS OF camping locality.

ANATOMISTS. Indeed, kindness itself has been displayed in every direction. All the authorities of the island have laid

THE first meeting of the Congrès fédératif interthemselves out to supply anything that is required,

national d'Anatomie was held in Geneva, and and already these offers have been accepted in several

commenced on the morning of Sunday, August 6, bt ways.

the opening of an exhibition of specimens and apOn the early morning of August 11 work at the pliances illustrating recent progress in anatom. camp began in earnest. The tents, loaned to us bv | The congress closed on the evening of Thursday the War Office, were taken ashore and erected, and August 10, when three hundred members and adlater in the day the packing cases were landed and herents of the congress were entertained by the city carried by carts to the ground. Parties from the ship of Geneva to an official banquet. The congress roa soon began to be acquainted with the contents of the presented a conjoint meeting of the five leading cases they had so delicately handled, and by the even anatomical Societies-the Anatomical Society of ing the large wooden structure composing the dark Great Britain and Ireland, Anatomische Gesellschaft, room and the camera end of the prismatic reflector, Association des Anatomistes, Association of and also the siderostats and calostat huts, were American Anatomists, and the Unione Zooligicu nearly all erected and covered. While this work was | Italiana. Almost every country was represented in progress, meridian lines were being pegged out Switzerland itself contributed more than 100 members, and the positions for the concrete pillars fixed. 1. France 06, Germany and Austria 36, Great Britain

and Colonies 23, Italy II, America 3, and other of the central nervous system. The cephalic part of countries 16. The largest contributors to the pro- . the central nervous system is seen at first not to be ceedings of the congress, however, were the Germans; differentiated into three parts, viz., hind-, mid-, and out of a total of 117 communications, 32 were made fore-brain, but into two, a hind part, or archenby them, 31 by the French, 18 by the British, 15 by cephalon, and a fore part, or deuterencephalon, under the Swiss, 8 by Italians, 5 by Swedes, and 2 by which the notochord terminates. The archencephalon Americans.

shows four or five sharply demarcated neuromeres in From every point of view the congress was a suc front of the neuromere connected with the facial cess. Anatomy is peculiarly susceptible of inter nerve (prefacial neuromeres), but Prof. Wilson denational treatment, the subjects for description and tects in some of them traces of a subdivision. There discussion being concrete and capable of direct demon are three post-facial neuromeres. By using emstration. The language difficulty certainly hindered bryos of Perameles and Dasyurus to supply blanks a free discussion on more than one occasion; for in in the ornithorhynchus series, Wilson and Hill were stance, on the second day, a speaker, after able to show that the neural crest forms at first a giving his communication in French, listened continuous hem on the lateral margins of the medulmost attentively to a vigorous criticism in lary plates. That part of the neural crest correspondGerman, and, bowing profoundly, replied, “Je ne ing to the prefacial neuromeres undergoes, relatively comprends pas l'allemand.” With an agenda list to the rest of the neural system, an enormous growth overloaded with 117 communications, there was a forming a plate of cells which was mistaken by grave risk of disorganisation. Thanks to the com- Selenka in other marsupial embryos for a mass of plete arrangements made by the committee of organic mesoblast. The neural crest connected with the sation, presided over by Prof. A. Êternod, of Geneva, facial segment forms the acoustic ganglion; that and to the perfect arrangement of business by the pre- with the post-facial neuromeres the glosso-vagal sident of the secrétariat, Prof. von Bardeleben, the ganglion, the rest of the crest becoming differenproceedings of the congress made an even and steady tiated into spinal ganglia. progress. The success of the congress must also be It is within the memory of even the younger ascribed to Prof. Nicholas, of Nancy, secretary of the zoologists that ornithorhynchus was regarded at one French society; English members were indebted to time as a toothless mammal; then came the disProf. Symington, president of the British society, covery by Poulton and by Stewart that teeth were and to Dr. Christopher Addison, its secretary. Each present but remained embedded in the gums. Prof. day's work was divided into two parts; the morning Wilson was able to demonstrate in his series of emwas devoted to papers, ten minutes being allowed forbryos the presence of two dentitions-the developeach communication, and three minutes to any mem- | ment and absorption of a milk dentition and the ber who wished to criticise; the afternoon was set formation of a permanent dentition--that discovered aside for exhibition of new specimens and demonstra- by Poulton and Stewart. Thus ornithorhynchus, so tions of the material on which the communications of far as its dentition is concerned, takes its place with the morning were based, and this was by far the diphyodont mammals. Further, it was shown that most instructive and profitable part of the day's work. | each cusp of the permanent molars is preceded by The Swiss cow-bell, employed by the president of a separate milk tooth-a powerful argument in each day's proceedings (for the president of each favour of the evolution of molar teeth by the consociety acted in turn as chairman) to warn the speaker crescence of single-cusped teeth. Photographs were that he had reached the limit of his allotted time, exhibited of a reconstructed model of the skull of a bound the members of the congress by a common fætal ornithorhynchus which shows many aberrant sense of humour and materially aided the success of and puzzling features. Other contributions to the the meeting. In spite of the entente cordiale, the embryology of monotremes were made by Prof. British anatomists associated more closely with the Keibel, of Freiburg (models showing the developGerman than with the French members of the con ment of the urogenital apparatus of echidna), and gressman association determined, for the greater to the embryology of marsupials by Dr. Für part, by the fact that the Germans were the superior Bresslau, of Strassburg (preparations showing the linguists.

development of the pouch of Didelphys marsupialis). With so extensive a programme, it is impossible in Two papers on the agenda list, one by Prof. von a report such as this to do more than note the more Bardeleben, of Jena, entitled, “ Die Homologie des outstanding communications. Making every allow Unterkiefers in der Wirbeltierreihe," the other by ance for prejudice of race, the first place, both in im- | Prof. Gaupp, of Freiburg, “ Die Nicht-Homologie portance of results and excellence of technique, must des Unterkiefers in der Wirbeltierreihe," brought be assigned to the contributions made by Prof. J. T. again into prominence that much-debated problemWilson, of Sydney University, who placed before the the origin and nature of the mammalian lower jaw. congress the results of a prolonged investigation into Bardeleben maintained that the lower jaw of a the developmental history of ornithorhynchus mammal was strictly the same structure as that of a made by his colleague and collaborator, J. P. | reptile, and produced, as evidence of his contention, Hill, and by himself. With the material now | mandibles of marsupials and of human fætuses in at their command they will be able to write a which there could be traced lines somewhat similar full and precise account of the development of to the sutural lines to be seen in the reptilian the monotremes and throw a great deal of light on mandible. Prof. Gaupp's paper was a clear and mammalian morphology. The photograph of an vigorous denial of Bardeleben's contentions. In ornithorhynchus egg, in the eight blastomere stage, Gaupp's opinion the temporo-maxillary joint of was shown. Most remarkable of all were the mammals was a new joint formed between the specimens and photographs showing the early de- coronoid process of the reptilian jaw and the velopmental phases of the central nervous system. squamosal, and quite different from the mandibuloThe medullary plates, instead of folding over at an quadrate joint of reptiles. His conclusions were early date to form the neural tube as in mammals largely based on a consideration of the relationship generally, remain exposed on the surface of the of muscles and nerves to these joints. The new embryo and thus give a superb opportunity of study- mammalian joint was formed in the insertion of the ing the processes of segmentation and differentiation pterygoideus externus, the end tendon of which be

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