268 



NATURE 



[December 21, 191 1 



rritical comparison of the overlapping section of the Oxford 

 and Potsdam Astrographic Catalogue. A number of plate*, 

 covering the richest region of the zone were wlertrd for 

 examination, and forty stars distributed all over thf over- 

 lapping area, but not too near the edges, were chosen. 

 'I'hese stars were between 8-5 mag. and 10 mag., so as to 

 be neither too bright nor too faint to give good images. 

 Two systems for obtaining the required solutions were 

 adopted and investigated, and the results compared, proper 

 motions b<'ing tftken into account. The author concluded 

 that the astrographic errors must be ascribed as much to 

 erroneous photographic places as to errors of meridian 

 catalogues. The errors in right ascension were smaller 

 than those in declination. 



Koyal Anthropological Institute, December 13. — Jotin 

 Qray : A new porigraph. In recent years anthropologists 

 have come to ihe conclusion that one of the best methods ! 

 of determining the racial afTinities and differences of two | 

 skeletons is to compare the outlines of their skulls and \ 

 other bones. It is necessary that these outlines should be 1 

 exact orthographic projections, and for this reason photo- { 

 graphs, taken by the ordinary camera, are unsuitable. 1 

 Various special instruments, known as " perigraphs," have I 

 been devised, chiefly by Continental anthropologists, for j 

 drawing these outlines, among the best known of which 1 

 are those of Martin, of Zurich, and Klaatsch, of Breslau. i 

 Most of these instruments suffer from certain defects. A i 

 new design has been introduced in the two forms of the 1 

 p-rigraph, exhibited and described by Mr. Gray, in which ! 

 advantage is taken of the well-known principle in | 

 mechanism that every point in a plate moving parallel to i 

 itself describes exactly similar curves. The application of j 



is principle enables the outline to be drawn at one side | 

 instead of under or over the skull, and the delicate adjust- j 

 ments of tracer and pencil in the older instruments are 1 

 r -ndered unnecessary. By an ingenious application of the 1 

 stereoscopic principle, Mr. Gray is able in one form of his | 

 instrument to draw contour lines, at any height, without i 

 touching the skull. 



. Mathematical Society. December 14.— Dr. H. F. Baker, 

 president, in the chair. — J. \V. Nicholson :' The pressure 

 of radiation on a cylindrical obstacle. — H. Hilton : 

 H-^rniitian invariants of a canonical substitution. — E. \V. 

 Kobson : The fundamental lemma of the calculus of varia- 

 tii)ns and some related theorems. — \V. Burnside : The 

 outer isomorphisms of a group. — E. B. Stouffer : In- 

 variants of linear differential equations. — J. C. Fields : .\ 

 mfthod of proving certain theorems relating to adjointness. 



Cambridge. 



Philosophical Society, November 27.— F, A. Potts: A 



luw type of parasitism in the Polycha'ta. A new genus 

 of the polychaet worms, here named Parasitosyllis, was 

 found by Mr. Cyril Crossland at Zanzibar in 1902 as an 

 ectoparasite on other polycha^ts and nemertines. .Attach- 

 ment is effected by the permanently protracted pharynx, 

 lined by very thick chitinous layers which penetrate widely 

 into the host, becoming quite inseparable from its tissues. 

 The lumen of the pharynx is very restricted, probably only 

 .illow-ing the passage of fluids, absorbed by the pumping 

 action of the proventriculus. — C. Shearer, H. M. Fuchs, 

 I.. Doncaster, and J. Oray : The experimental hybridisa- 

 tion of echinoids. (i) General account of the experiments 

 (C. Shearer). (2) The chemical control of inheritance in 

 echinoid hybrids (H. M. Fuchs). The authors described 

 the results of experiments on the hybridisation of echinoids 

 conducted at Plymouth. From a study of the characters 

 of the late larva, which are much more definite than the 

 early characters used by previous investigators, they 

 showed that the inheritance of the parental characters in 

 the hybrids was strictly maternal. (3) Cytological observa- 

 tions of hybrid echinoid eggs (L. Doncaster and J. 

 Gray). Cross-fertilised eggs, Echinus acutiisxE. escu- 

 lentus, E. esculentusxE. acutus, and E. acutusxE. 

 miliaris, were examined in the early segmentation stages 

 to discover whether omission of chromosomes such as has 

 b"en described by Baltzer occurs in these crosses. In 

 E. esculentusxE. acutus the mitotic figures were quite 

 normal. In th'^ converse cross a varying number of 

 chromosomes swell up and develop vesicles in the late pro- 



r,-o. 2^99, VOL. 88] 



phase stages. These vesicle* may be thrown ofT or p.ik <iii 

 attached to the chromouome ; when thrown off th<;. 

 frequently left on the outside of the spi-""- ""■' 

 included in 'he daughter nuclei. Some 

 chromosomes which have produced vesi- 

 sequentiv divide and behave normally. In E. acului 

 fertilised by E. miliaris a similar but less regular nr<' 

 spicuous formation of vesicles takes ]>'. ' 



Hemar : Note on the condensation of tr 

 certain aldehydes. Crystalline derivatives <i 

 have been prepared by the interaction of its aq; 

 tion with (a) formaldehyde, (6) glyoxylic acid. 

 glyoxal. Another derivative has been isolated as thf 

 of (d) the local heating of a layer of ether resting < 

 surface of an aqueous solution of tryptophane. Tli 

 an interesting relationship between the substances f 

 in the reactions (a), (6), and (d). Hydrolysis of the 

 aldehyde derivative and the action of heat on the gl;- 

 derivative result, in each case, in the format!"" • 

 compound isolated in the reaction (d). The ii 

 of the properties of these substances has shown ' 

 .-Xdamkiewicz, or glyoxylic, reaction the substance esbenli.i 

 to the production of the violet colour is formaldehyde. 



Paris. 

 Academy of Sciences, I)ecemb<»r 4. — M. Armand r- •• - 

 in the chair. — H. Poincar^ : The theory of the 

 A study of the hypothesis deduced by Planck from hi- 

 of the law of radiation of black bodies. According : 

 theory, the elements to which the radiation of incami 

 solid bodies would be due could only acquire or lose th> ir 

 energy by abrupt steps. This theory could not be •ex- 

 pressed by differential equations ; and the autho: ' 

 attempted to obtain the Planck law by other hyp' 

 with this limitation removed, but with negative re^.... ^ 



L. Lecornu : The balancing of motors. The problem of 

 balancing motors arranged as in aeroplanes is more difficult 

 than balancing a motor with parallel cylinders. It is 

 shown that the desired result can be theoretically obtained 

 by the addition of two or three auxiliary masses, fixed to 

 suitable points. — A. Laveran : Concerning Trypanosoma 

 rhodcsiense. A study of the trypanosome discovered in 

 Rhodesia by Stephens and Fantham. From the facts 

 described, particularly the observations which demonstrate 

 that an animal having acquired immunity for T. 

 gambiense is infected like a new animal by T. rhodesiense, 

 that the last trypanosome cannot be identified with 

 T. gambiense. Experiments are in progress having for 

 their object a similar comparison of T. rhodesiense with 

 T. brucei. — A. Miintx and E. Lain* : The proportion of 

 carbon dioxide in the air of the Antarctic regions. Samples 

 collected between latitudes 64° and 70° show a mean con- 

 tent of 2-05 parts of carbon dioxide per 10,000, the lowest 

 proportions occurring in the highest latitudes. These re- 

 searches, and those obtained some time ago in latitude 

 55°, in the neighbourhood of Cape Horn, afford a striking 

 confirmation of the views of Th. Schlcesing on the ex- 

 changes of carbon dioxide between sea water and air.— j 

 M. Lannelongrue : Excavations at the hamlet of S^viac*^ 

 near Montr(?al (Gers). Discovery of a big toe in broni 

 The excavations have disclosed some mosaics in a 

 state of preservation. Details are given of a bronze 

 which was found on the soil, and is remarkable for 

 vigour and anatomical exactness. It is surmised that 

 may be an ex-voto annexed to a statue in stone or marl 

 or it may be a fragment of an important bronze statue,; 

 M. Moureu was elected a member of the section of che 

 istry in the place of the late M. Troost. — MM. 8cl 

 masse and Javelle : A new comet discovered by 

 Schaumasse at the Obser\'atory of Nice, and observed 

 ^•M Scbaum.Tso' and lavelle. This comet was found 

 November 30 with the bent 40-cm. equatorial, and' appes 

 as a circular nebulosity 3' to 3-5' diameter, with a bmi 

 defined nucleus of about the twelfth magnitude. T' 

 apparent positions are given for November 30 ami 

 December i. — E. M. AntoniadI : Observations of the 

 planet Jupiter in 191 1 with the 83-cm. equatorial of the 

 Observatory of Meudon. A detailed description of the 

 planet is accompanied with five illustrations of points of 

 interest. — H. Deslandres : Remarks on the preceding 

 communication and on the utilitv nf tHp nh*. rvation of the 



