June 4, 1903] 



NATURE 



119 



author examined a specimen of an allied species obtained 

 by Dr. Th. Mortensen from an island in the Gulf of Siam. 

 These two new species, Ingolfiella ahyssi and Ingolfiella 

 littoralis, one abyssal from the North Atlantic, the other 

 from shallow water in the Pacific, agree in being extremely 

 minute. — On the evolution of the Australian Marsupialia ; 

 with remarlts on the relationships of the marsupials in 

 general, by Mr. B. Arthur Bensley. The paper contains 

 a minute description of the dentition of more than forty 

 genera, and treats also of the structure of the hind foot. 

 Mr. Bensley considers that the primary division of the 

 Marsupialia should be based on the condition (syndactylous 

 or eleutherodactylous) of the second and third digits of the 

 hind foot, rather than on the condition (polyprotodont or 

 diprotodont) of the incisor teeth ; and he is disposed on 

 this account to associate the Peramelidae more closely with 

 the Phalangeridae than has hitherto been customary. The 

 author regards the Australian marsupials as probably 

 monophyletic, and considers, with Winge, that the ancestral 

 forms were primitive members of the Didelphidae, a family 

 which must have had a wide geographical distribution in 

 past times. A study of the dentition impels him to the 

 conclusion that the primitive types were all insectivorous, 

 but that the subsequent radiation, or divergent evolution, 

 proceeded along two primary lines, one carnivorous, culmin- 

 ating in Sarcophilus, the other omnivorous and finally 

 herbivorous. In the second line all of the advanced forms 

 are diprotodont, and all of the typical terminal forms are 

 highly specialised herbivora. — Copepoda Calanoida, chiefly 

 abyssal, from the Faroe Channel and other parts of the 

 North Atlantic, by Canon A. M. Norman, F.R.S. Most 

 of the Copepoda mentioned were procured by Sir John 

 Murray in the Triton expedition of 1882, at various depths 

 to 600 fathoms ; a few were from the Valorous expedition 

 of 1875 ; the remainder from a gathering sent by Prof. 

 Haddon from 200 fathoms forty miles N.N.W. of Achill 

 Head. Some of the specimens have been examined and 

 named by Prof. G. O. Sars, and the great interest of the 

 observations now laid before the Society consists in the 

 record of the geographical distribution of these small but 

 •ever active crustaceans. Thus, some of the Faroe Channel 

 •species found at considerable depths were taken by 

 F. Nansen near the surface at the point reached by him 

 nearest the Pole ; the varying depths at which these 

 organisms occur constitute isothermal lines, which largely 

 determine their dispersion. 



Dublin. 



Royal Irish Academy, May 11. — Prof. Atkinson, presi- 

 <ient, in the chair. — Captain G. E. H. Barrett-Hamilton 

 read an abstract of some results of his researches into the 

 meaning of winter whitening in mammals and birds in- 

 habiting snowy countries, and the occurrence of white 

 markings in Vertebrates generally. He finds that the first- 

 named coloal--change is not a merely external factor having 

 as its purpose the adaptation of the animal to its environ- 

 ment, but a peripheral atrophy symptomic of deep physio- 

 logical changes occurring in species possessing a meta- 

 "bolism which varies with the season. Thus the white 

 colour affects the different parts of the body in the same 

 -order as that in which subcutaneous fat is accumulated in 

 the panniculus adiposus. The author further finds a con- 

 nection between much of the permanently white parts of 

 Vertebrates and the accumulation of subcutaneous fat. 

 Such white colour is then due to peripheral atrophy. This 

 atrophy may manifest itself either in deficiency of pigment 

 or in complete absence of hair. — Captain Barrett-Hamil- 

 ton also read a description of a remarkable addition to the 

 list of British mammals of boreal type. This is a bank 

 vole (Evotomys) inhabiting the small island of Skomer, off 

 the coast of Pembrokeshire. — Mr. G. H. Carpenter read 

 a paper on the relationships between the classes of the 

 Arthropoda. In opposition to certain recent speculations as 

 to the independent origin of insects, arachnids, and crus- 

 taceans from annelid worms, the author advocates a 

 common .\rthropod ancestry for the various classes. The 

 conclusion drawn from the numerical agreement in seg- 

 mentation between typical members of the three great 

 Arthropod classes is that the ancestral arthropods pos- 

 -3essed such a definite and limited number of segments, and 



NO. 1753, VOL. 68] 



that those groups with a large number of segments, such 

 as most centipedes and millipedes, and many branchiopoda 

 and trilobites, represent abnormal developments. 



Paris. 

 Academy of Sciences, May 25. — M. Albert Gaudry in 

 the chair. — The action of acetylene upon caesium-ammonium 

 and rubidium-ammonium. The preparation and properties 

 of the acetylenic acetylides Cj.Csj.CjHj, C^Rbj.CjH,, and 

 the carbides of caesium and rubidium, by M. Henri 

 Moissan. By the action of acetylene upon solutions of 

 ciEsium and rubidium-ammonium compounds of the type 

 CjRj.CoHj are formed, from which the carbides CjRj can 

 be obtained by heating in vacuo. These carbides react with 

 water, giving the alkali and pure acetylene ; they are ex- 

 tremely energetic reducing agents, acting upon the per- 

 oxides of lead and manganese with explosive violence. — 

 The influence exerted on the rotatory power of cyclic mole- 

 cules by the introduction of double linkages into the nuclei 

 containing the asymmetric carbon atom, by M. A. Haller. 

 The condensation products obtained by acting upon methyl- 

 hexanone with aldehydes in presence of sodium methylate 

 have been examined for their rotatory power. The effect 

 of the double linkage is in every case to increase the rota- 

 tion. — On new sources of radiations capable of traversing 

 metals, wood and other substances, and on the new actions 

 produced by these radiations, by M. R. Blondlot. By 

 applying the method described in an earlier paper, using 

 the electric spark as a detector, radiations similar to those 

 detected in the light from an incandescent mantle have 

 now been found to be emitted from an ordinary Argand 

 burner, and from a sheet of incandescent silver. The effects 

 are observed after the radiations have passed through 03 

 mm. of aluminium, black paper, &c., and in the case of 

 the polished silver sheet are polarised, but the polarisation 

 disappears when the silver is covered with lamp black. 

 The name n-rays is suggested for these radiations. The 

 n-rays are incapable of exciting phogphorescence in bodies 

 which acquire this property under the action of light, but 

 sulphide of calcium, already slightly phosphorescent, shows 

 an increase in lustre when exposed to these rays. — M. 

 Munier-Chalmas was elected a member in the section of 

 mineralogy in the place of the late M. Hautefeuille. — On 

 the development of a given function in series by means of 

 Jacobi polynomials, by M. W. SteklolT. — On the integra- 

 bility of a differential expression, by M. P. Montel. — On a 

 theorem of Lejeune-Dirichlet, by M. A. Pellet. — On double 

 cylindrical networks, by M. L. Raffy. — On the deformation 

 of surfaces, by M. Maurice Servant. — The law of displace- 

 ment of thermodynamic equilibrium, by M. E. Arids.— 

 On the simultaneous variation of solar spots and terrestrial 

 temperatures, by M. Alfred Angrot. If at any given station 

 the mean annual temperatures, t, present a variation parallel 

 to the number of sun-spots, r, the relation t = t„ + ar will 

 hold approximately, t„ and a being constants characteristic 

 of the station. This formula is applied to ten years' observ- 

 ations from Guadeloupe. — The thermal conductivity of crystal- 

 lised bismuth, by M. F. Louis Perrot. The conductivity 

 is greatest perpendicular to the axis, and in the direction 

 of the line of easiest cleavage. — On Hertzian waves in wire- 

 less telegraphy, by M. G. Ferrid. — On the polarised light 

 diffused by refraction, by M. A. Lafay. — On the combined 

 hydrogen contained in reduced copper, by M. Anatole 

 Leduc. Five litres of air passed over a column of red-hot 

 copper, in such a manner as to ensure superficial oxidation 

 along its whole length, still leaves a weighable amount of 

 hydrogen in the copper. — On the decomposition of lithium 

 carbonate by heat, by M. P. Lebeau. Dissociation of 

 lithium carbonate commences at about 600°, the dissocia- 

 tion pressure increasing to 91 mm. at 1000° C, and 

 approaching 300 mm. at 1200° C. An attempt to prepare 

 lithium oxide by healing the carbonate in a vacuum at 

 1000° was unsuccessful, as the oxide is itself volatile at 

 this temperature, in which respect lithia is sharply differen- 

 tiated from the alkalies and alkaline earths. — The electro- 

 lysis of barium sulphide with a diaphragm, by MM. Andr^ 

 Brochet and Georges Ranson. Polysulphides of barium 

 are formed at the anode, and baryta at the kathode. The 

 latter being placed in a porous pot, the baryta is obtained 

 in a pure state, — On the mode of splitting up of mixed 

 organo-magnesium compounds ; the action of ethylene 



