December i, 1898] 



NA rURE 



119 



australc, have been found in association with the radiolaria. 

 These New South Wales radiolarian deposits are by far the 

 most extensive of any hitherto known, and they are remarkable 

 not only for their great thickness, but also for the manner in 

 which the radiolaria are preserved in the limestones, tuffs, and 

 claystones. 



Cambridge. 

 Philosophical Society, November 14. — Mr. J. Larmor, 

 President, in the chair. — Orthogenclic variations in the cara- 

 pace of Chelonia, H. Gadow. Dr. Willey had brought home 

 twenty very young specimens of the Loggerhead Turtle, Thalas- 

 sochelys caretta. This material has been supplemented by the 

 examination of the specimens in the British Museum and the 

 Cambridge Museum of Zoology. In all fifty-six specimens have 

 been examined, consisting of forty-one very young, and others 

 ranging from three inches to the full-grown turtle of about four 

 feet in length of shell. This species exhibits a great amount of 

 variation in the number and size of the epidermal shields which 

 cover the shell. The variations are most numerous in the 

 young, least so in the adult. They can be reduced to a system, 

 each variation representing an atavistic or phyletically older 

 stage, the greater number of shields being the more primitive. 

 The reduction in numbers proceeds in a definite way, until the 

 normal number (namely that which is found in most adult 

 specimens) is reached. Hence the 'term " orthogenetic varia- 

 tion.' — Some points in the morphology of the Enteropneusta, 

 A. Willey. The body-wall of Enteropneusta is characterised 

 externally by annulations determined by the zonary disposition 

 of epidermal glands and separated by interannular grooves. The 

 potentialities of these structures are indicated by the external 

 liver-saccules of Ptychoderidae, which are enlargements of the 

 annulations ; and by the dermal pits of Spengelia, which are 

 intergonadial depressions of the interannular grooves. In the 

 Enteropneusta and in the Cephalochorda the gonads are more 

 or less coextensive with the gill-clefts, both being primarily un- 

 limited in number. A theory of gill-slits was developed, 

 according to which gill-slits arose in the interannular depres- 

 sions, while the gonads were disposed in zones corresponding 

 with the epidermal annulations. The primary function of the 

 gill-slits was the oxygenation of the gonads, their secondary 

 functions being the respiration of the individual. In mo.st cases 

 the gonads have been secondarily emancipated from the gill- 

 clefts in correlation with the elaboration of the vascular system. 

 In the author's opinion the evidence in support of this theory 

 is overwhelming. A collective name, Branchiotrema, was 

 introduced to include all animals which possess gill-slits, 

 whether in the adult or in the embryo. — On I.epidodendron 

 from the Calciferous Sandstone of .Scotland, A. C. Seward and 

 A. W. Hill. A description was given of the anatomy of an 

 unusually well preserved stem of Lcpidodendron Wiinschianiini 

 recently found in a railway cutting at Dalmeny in Linlithgow- 

 shire. The stem measures nearly 40 cm. in diameter, the outer 

 bark is well-preserved, but the more delicate middle cortex was 

 destroyed before petrification ; the innermost cortex and the 

 central cylinder show remarkably perfect structure. One of the 

 important characters noticed in the stem was the structure of 

 the leaf-trace bundles ; these consist of a small strand of xylem 

 more or less completely surrounded by radially disposed rows of 

 secondary elements. The presence of numerous secretory 

 canals in the outer cortex or phelloderm was also referred to as 

 a feature of some interest. 



Paris. 



Academy of Sciences, November 21. — M. Wolf in the 

 chair. — On some relations between luminous and chemical 

 energy, and on the displacements between oxygen and the 

 halogen elements, by M. Berthelot. The decomposition of 

 iodic acid into its elements is a reaction which cannot be re- 

 versed by sunlight, either dry or in presence of water. The 

 reaction between bromine and water is almost unmeasurable in 

 the dark, but becomes sensible in sunlight. The reverse reaction 

 between hydrobroniic acid and oxygen can be shown to take 

 place in sunlight to a small extent. — On the atomicity of boron, 

 by .Sir Edward Frankland. .S^>me remarks on the substance 

 described by M. Copaux in the last number of the Coinptes 

 rendiis, arising from the reaction between sodium elhylate and 

 ethyl borate. The formula (CJI,,) (ONaj.BiOCjHslj would ap- 

 pear to be more probable than that suggested by M. Copaux. — 

 On observations of the Leonid meteors, made from a balloon 

 during the night of November 13 to 14, by M. J. Janssen. 



NO. I 5 18, VOL. 59] 



Although, by reason of the cloudy state of the sky, 

 the night of November 13 was very unfavourable for 

 observations from the ground, good results were obtained 

 from a balloon at a height of 150 to 200 metres, about 

 twenty-five Leonids being noted. — On the determination of the 

 latitude of the Observatory of Paris by the methods of M. Loewy, 

 by MM. H. Renan, J. Perchot, and W. Ebert. The method 

 used has the advantage over the usual one of measuring the 

 superior and inferior culminations of circumpolar stars of giving 

 results based on night observations only. — Observations of the 

 planet DQ (433), made at the Observatory of Paris, by M. G. 

 Bigcmrdan. — Elements of the planet DQ (433), calculated by M. 

 G. Fayet. — Observations of Leonids, made on November 14 at 

 the Observatory of Lyons, by M. Ch. Andre. — On differential 

 systems of which the integration can be reduced to that of total 

 differential equations, by M. Riquier. — An experiment repro- 

 ducing the properties of magnets by means of combinations of 

 vortices, in air or in water, by M. Ch. Weyher. The bars 

 representing the magnets have a wooden axis, upon which are 

 fastened strong paper vanes along its whole length. A similar 

 bar set in rotation attracts or repels the first, according as the 

 directions of rotation are the same or opposite ; the two showing 

 the neutral zone and other properties of magnets. — On the 

 induction machines used as generators or receivers of alternating 

 currents, either simple or polyphase, by M. Maurice Leblanc. 

 — Characterisation of diabetic sugar in urine, by M. Le Goff. 

 The sugar was isolated from the urine by filtration and evapora- 

 tion in a vacuum to a syrup, from which crystals separated after 

 a fortnight. These crystals were washed with alcohol, then dis- 

 solved and treated with animal charcoal, and crystallised out 

 slowly in vamo. The sugar thus obtained had the composition 

 CnHjoOg 4- ^H„0,| for which the rotatory power was (aJD = 

 -^ 49°"46. The osazone formed needles, melting at 230°, and 

 oxidation yielded gluconic acid, (o)n = 4- 6"53. These results 

 show that the sugar present in diabetic urine is undoubtedly 

 (/-glucose. — The utilisation of the phosphoric acid dissolved in 

 the waters of the soil by plants, by M. Th. Schloesing, jun. In 

 sterilised soil, which has been treated with solutions containing 

 all the elements necessary for plant growth except phosphoric 

 acid, plants will not develop naturally, but in presence of solu- 

 tions containing in addition quantities of phosphates of the order 

 of those contained in arable earth, the plants flourish, — General 

 conclusions on humic coals, by M. C. Eg. Bertrand. — On the 

 constitution of peat, by M. B. Renault. The black peat studied 

 consists of microscopical debris of plants arising from 

 the tougher tissues, such as cuticle, spores, and pollen 

 grains, the other tissues having generally disappeared 

 under diverse influences, especially microbial action. The 

 wood found in peat bogs has undergone a profound modi- 

 fication ; its tissue is permeated with the mycelium of micro- 

 scopic fungi, and numerous micrococci are present. — Artificial 

 production of pearls in the Haliotis, by M. Louis Boutan. By 

 the introduction of foreign bodies into Haliotis, true pearls can 

 be produced. — On a method of colouring protoplasm by bacterial 

 pigments, by M. L. Matruchot. By growing together on the 

 same medium, a chromogenic bacterium (violet pigment) and a 

 filamentous fungus, an impregnation of the protoplasm of the 

 latter by the pigment can be obtained, and as the colouring 

 matter is selective and is fixed only by a part of the protoplasm, 

 this treatment constitutes a true method of coloration allowing 

 the study of the structure of living protoplasm. This method 

 has been applied by the author to a species of Mortierella. — 

 On the black phosphates of the Pyrenees, by M. David Levat. 

 h. description of the nature of the deposit, and analyses of the 

 phosphatic nodules. The nodules are black, resembling anthra- 

 cite in appearance, and consist of nearly pure calcium phosphate. 

 — On the presence of fossil layers containing species of Physa 

 and Limnoea in the Lower Eocene of Corbieres, by M. A. 

 Bresson. — On the parallelism of the Urgonian limestones with 

 the Cephalopod layers in the Dephino-rhodanian region, by 

 M. Victor Paquier. , 



Amsterdam. 

 Royal Academy of Sciences, October 29. — Prof, van de 

 Sande Bakhuyzen in the chair. — Prof. D. J. K-^rleweg made 

 some remarks upon the progress in the prepaiation for the 

 International Catalogue since the Conference of July 1896. 

 Special mention was made of some of the resolutions passed in 

 the Conference of October 11 to 13. — Prof. Winkler made a 

 communication entitled "Attention and Respiration," which 

 will be inserted in the Report of the meeting. — Prof, van der 



