Jan. lo, 1889] 



NATURE 



263 



contributed a paper on Apiocystis, which he regarded as a 

 Volvocinea. The ciliated form was described, and it was shown 

 that its zoospores may sometimes escape as ccenobia, like a 

 degenerate Volvocinea which has exchanged the motile for the 

 fixed condition. The sexual cells being zoogametes, its affinity is 

 rather with Pandorinei? than with oogamous Volvocect. The 

 paper was criticized by Mr. A. W. Bennett and Prof. Marshall 

 Ward, who, while testifying to the importance of the investiga- 

 tion, expressed the hope that no change would be made in 

 classification until further examination had been made of some 

 of the stages at a critical period of development. Mr. George 

 Murray gave his warm support to the views expressed by Mr. 

 Moore. — A paper was then read by Mr. G. B. Sowerby em- 

 bodying descriptions of some new species of shells, of which 

 coloured drawings were exhibited. Amongst these, the most 

 noticeable were an Orthalictis from the Peruvian Andes, 

 Pleurotoma (Hong Kong), Amaihina (Mauritius), Crassatella 

 (Japan), Clavigclla (Mauritius), and Pcctuncidus (Australia): 

 An interesting' discussion followed, in which Prof. Stewart 

 and Prof. Mivart took part, upon the coloration of MoUusca 

 being possibly dependent upon the colour of tlieir natural 

 surroundings, or upon that of the host to which in many instances 

 they were found to be attached. 



Geological Society, December 19, 1888. — W. T. Blanford, 

 F.R.S., President, in the chair. — The following communications 

 were read : — Trigonocriniis, a new genus of Crinoidea from the 

 "Weisser Jura" of Bavaria, with description of new species, 

 T. lirattis ; Appendix I. Sudden deviations from normal sym- 

 metry in Neocrinoidea ; and Appendix II. Marsupites tcstudin- 

 arius, Schl., sp., by F. A. Bather. This genus is proposed on 

 the evidence of two calyces in the British Museum (Natural 

 History) which were found among specimens of Eu^eniacrinus 

 from Streitberg. The species of Eugeniacrinus, Phyllocrinus, 

 and Trigonocrinus may be arranged in a series which is ap- 

 parently one of evolution. The present genus is, therefore, to 

 be placed with the Eugeniacrinidse, although its characters are 

 not tho.>e of the family as heretofore defined. This is seen 

 from the following diagnosis : Trigonocrinus, gen. nov. Calyx 

 roughly triangular or trilobate in section. Basals 4, but one so 

 atrophied as to be almost invisible ; all fused into a basal ring. 

 First radials 4 ; the two on either side of the smallest basal half 

 the size of the others, thus maintaining the triangular symmetry ; 

 all closely united, with each suture-line in a groove. Processes 

 of radials well developed, forming spines homologous with the 

 petals of Pkyllocrinus ; except the adjacent processes of the 

 smaller radials, which only form a minute ridge. Articular 

 surface of radials curved gently inwai-ds and upwards ; muscular 

 impressions indistinct or absent ; no articular ridge ; no canal- 

 aperture. Arms unknown (? represented by fleshy appendages). 

 Calycal cavity contained in first radials ; with small round ventral 

 aperture, surrounded by a rim, which is the only relic of a 

 muscular attachment. Stem unknown. The two calyces belong 

 to the same species, viz. T. liratiis, sp. nov. Calyx rather more 

 elongate than in the known species of Phyllocrinus ; basals orna- 

 mented with minute granules ; radials ornamented with similar 

 granules run into curved ridges, which, owing to their differing 

 intensity, give an imbricated appearance ; spines, triangular in 

 section, with the base of the triangle directed inwards, the 

 aoex outwards, the angles often rounded. The differentiation 

 of Trigonocrinus from the central Eugeniacrinid type has been 

 effected on the one hand in accordance with the principles of 

 "Degeneration," "Reversion," and "Use and Disuse"; 

 while, on the other hand, it exemplifies certain methods of 

 change in organic forms, which may be referred to the categories 

 of (l) sport, (2) hypertrophy and atrophy, (3) fusion and fission. 

 Thus considered it is of unique interest among Crinoidea. 

 An examination of the variations in symmetry presented by the 

 Echinodennata suggests the conclusion that the Pentamerous 

 type was originally evolved from another system, or at least that 

 it was selected from among other variations, that it has sur- 

 vived, and that it has been kept true, as being the fittest. 

 Appendix I. Sudden deviations from normal symmetry in Neo- 

 crinoidea. A collection of instances from previous authors, with 

 a few additions, the whole illustrating the latter portion of the 

 paper. Appendix II. On Marsupites testudinarius, von 

 Schlotheim, sp. A synonymy of the genus Marsupites ; it con- 

 tains but one known species, and all other names must yield to 

 this one. After the reading of this paper the President welcomed 

 a new ]iala?ontologist to the Society, and some comments on the 

 author's views were offered by Dr. P, H. Carpenter and Prof. 



Seeley. — On Archaocyathus, Billings, and on other genera 

 allied thereto, or associated therewith, from the Cambrian strata 

 of North America, Spain, Sardinia, and Scotland, by Dr. G. J. 

 Hinde. — On the Jersey brick clay, by Dr. Andrew Dunlop- 



Paris, 

 Academy of Sciences, December 31, 1888. — M. Janssen 

 in the chair. — Mean elevation of the continents and mean 

 oceanic depths in relation to geographical latitude, by Gc^neral 

 Alexis de Tillo. Tables are given of the mean elevations and 

 depths, in metres, for every zone of 10° of latitude from pole 

 to equator in the northern and southern hemispheres, based 

 on J. G. Bartholomew's hypsometric chart of the globe. The 

 greatest mean heights and depths are found in the northern 

 hemisphere, between 30° and 40° ; in the southern, between 10° 

 and 30°, which also correspond to the zones of greatest atmo- 

 spheric action and mean annual pressure. The mean height of 

 the dry land and the mean oceanic depth for the globe are found 

 to be, respectively, 693 and 3803 metres. — Observation of 

 shooting-stars for the period August 9- 1 1, 1888, in Italy, by 

 Pere F. Denza. The results are tabulated of the records taken 

 at twenty-nine Italian stations, showing the number of meteors 

 observed in the space of one hour during the periodic showers 

 on the nights of August 9, 10, and 11, 1888. These results 

 differ considerably for the different stations, owing to the varying 

 state of the atmosphere, the experience of the observers, and 

 other causes ; but, on the whole, the meteoric shower was toler- 

 ably copious compared with those of previous years. — On the 

 volumes of saturated vapours, by M. Ch. Antoine. From the 

 general relation established by Zeuner between the pressure 

 and volume of aqueous vapour, formulas are here determined 

 for the volumes of the vapour of water, ether, acetone, chloro- 

 form, chloride of carbon, and sulphide of carbon. — Propagation 

 of the electric current on a telegraph line, by M. Vaschy. 

 From a consideration of Sir W. Thomson's theory of propaga- 

 tion applied to long submarine lines, it is generally inferred that 

 the currents are propagated along the line ivillioiit change of 

 form, their amplitude alone decreasing in geometric progression. 

 An important practical consequence of this result is indicated 

 for the working of telegraph lines, and this is stated to be also 

 applicable lo telephonic messages. — Action of sulphuretted 

 hydrogen on the sulphate of zinc in a neutral or acid solu- 

 tion, by M. H. Baubigny. A current of hydrosulphuric gas 

 passed through a saturated solution of zinc causes a portion of 

 the metal to be precipitated ; but the action is arrested when 

 the solution becomes acid to a certain point of intensity. This 

 statement of Berzelius is correct enough, as thus expressed. But 

 the law deduced from its generalization for all cases is here 

 shown to be false, and completely at variance with experience, 

 especially when the solutions are diluted. — Artificial reproduction 

 of chromiferous iron, by M. Stanislas Meunier. After repeated 

 failures, the author has at last succeeded in obtaining this substance 

 [chromite) by combining the protoxide of iron obtained from the 

 carbonate with the sesquioxide of chromium obtained by the 

 reduction of the bichromate of potassa. — A chemical study of the 

 Algerian soils, by M. A. Ladureau. A careful analysis of 

 samples from various parts of Algeria shows a general dearth of 

 phosphates, which explains the inferior quality of the cereals 

 grown in that colony. — Combination of the glycol-alcoholate of 

 soda with glycol, by M. de Forcrand. The author has already 

 shown that many alcoholates unite with one or rnore molecules of 

 a monatomic alcohol to form more or less stable crystalline com- 

 pounds analogous to the acid salts, and to the numerous hydrates 

 of the salts, bases, or acids. Here, he shows further that glycol 

 may combine in the same way with the glycol-alcoholate of soda 

 at equal equivalents. — On the active crystalline substance ex- 

 tracted fioni the seeds of the smooth or hairless Strophanthus of 

 the Gaboon, by M. Arnaud. An analysis of this substance, 

 used by the Pahouins (Fans) for poisoning their arrow-heads, 

 shows its close affinity to the wabaine of Acokanthera IVabaio 

 from Somali-land, and the strophanthine oi Strophanthus Kombi, 

 from Senegambia, previously described by the author. — Bio- 

 logical and therapeutic experiments on cholera, by M. W. 

 Loewenthal. A series of experiments undertaken last year with 

 the cholera bacillus seems to show that salol might be advan- 

 tageously administered both as a prophylactic and a therapeutic 

 during the prevalence of the cholera epidemic. — On a deposit of 

 fossil bones in the Island of Samos, contemporaneous with the 

 Pikermi age, by Mr. Forsyth Major. This find is the result of 

 a scientific exploration of some islands in the .^Egean in the year 

 1887. It comprises some forty species of mammals, some of 



