December 17, 1914] 



NATURE 



441 



Mathematical Society, December lo. — Sir Joseph 

 Larmor, president, in the chair. — E. H. Neville : 

 Simultaneous equations, Hnear or functional. — Prof. 

 W. Burnside : Cyclotomic quinquisection. — Prof. D. 

 Buchanan : Oscillations near the isoscles triangle — solu- 

 tion of the three-body problem.— Prof. E. T. Whittalier : 

 Larne's differential equation and ellipsoidal harmonics. 



Ca.vibridge. 

 Philosophical Society, November 23. — Prof. Newall, 

 president, in the chair. — F. A. Potts : The colour 

 variations of the fauna associated with crinoids. The 

 commensals of the crinoid Comanthtis anniilatum, 

 which is found in vast numbers on the reefs of Torres 

 Straits, include amongst the Crustacea two species of 

 Alpheids, three Galatheids, a Periciimenes, an Isopod, 

 and an Amphipod. There are also brittle-stars, a 

 polychaet, and many Myzostomids. In most cases the 

 cornmensals match the host in colour and arrange- 

 ment of the markings. As the crinoid varies from 

 very light- to dark-coloured types there is also a great 

 variability in the commensals. In the Crustacea there 

 is an alternation of darkly pigmented stripes with 

 non-pigmented areas, and the relative proporjtions of 

 these vary with the coloration of the host. The 

 phenomenon is best studied in the two species of 

 Synalpheus. — Dr. H. B. Fantham and Dr. Annie 

 Porter : Some insect flagellates introduced into verte- 

 brates. Insect flagellates, e.g. Herpetomonas jaculum, 

 Leger, from Nepa cinerea, and H. ctenocephali, 

 Fantham, parasitic in the dog-flea, Ctenocephalus 

 canis, can live inside certain vertebrates {e.g. mouse 

 and dog respectively), and can multiply therein. This 

 the authors have shown experimentally. If such 

 flagellates be inoculated intraperitoneally or are fed 

 by the mouth in food, the flagellates can find their 

 way into the blood-stream and internal organs {e.g. 

 liver, spleen, bone-marrow) of the vertebrate host. 

 The insect flagellates are pathogenic to the verte- 

 brates experimented upon, producing symptoms like 

 those of leishmaniasis (kala-azar). The oval, post- 

 flagellate forms appear to be more capable of develop- 

 ing in vertebrate hosts than are other stages of the 

 herpetomonad parasite of the insect. It may be ex- 

 pected that the various leishmaniases, occurring in 

 different parts of the world, will prove to be insect- 

 borne herpetomoniases. — W. R. Thompson : Some 

 notes on insect parasites. These notes deal with the 

 question of the cuticula of the Arthropods as a means 

 of defence against parasites. An attempt was made 

 to show that by its thickness and resistance, by the 

 cuticular appendages such as spines and hairs, and 

 by the process of the moult which is in strict cor- 

 relation with the development of the cuticula, a very 

 considerable part of the parasitic invasion is arrested. 

 The heavy parasitism to which the Arthropoda are 

 often subject was held to be due in part to the fact 

 that many of the parasites are also Arthropods in- 

 habiting the same environment as their hosts, in part 

 to the structure and physiology of the Arthropods 

 themselves, which off'er as hosts an environment 

 especially favourable to the development of parasitic 

 organisms. — G. L. Purser : Preliminary notes on some 

 problems connected with respiration in insects gener- 

 ally and in aquatic forms in particular. Aquatic 

 insects were separated into two groups, true and false, 

 according as they made use of the oxygen in the pond- 

 water or not. Among the true group were mentioned 

 Sialis, Gyrinus, and the Trichoptera, which have the 

 simplest type of tracheal gill. The Ephemeridae and 

 Odonata were shown to have lamellate gills in which 

 a pigment, which has been named Spadicin, is pre- 

 sent. No explanation of its function has stood the 

 test of facts except a respiratory one, but evidence 



. NO. 2355, VOL. 94] 



for this is indirect only. The blood-gills of Chiro- 

 nomus were mentioned, and the question of the origin 

 of a treacheal system and the problem of ecdysis of 

 the tracheal system in true aquatic forms were dis- 

 cussed. — N. Wiener : The shortest line dividing an area 

 in a given ratio. 



P.^RIS. 



Academy ol Sciences, November 30. — M. P. Appell in 

 the chair. — Gaston Darboux : The integration of a 

 partial differential equation of the second order with 

 two independent variables. — Andre Blondel : The cal- 

 culation of the potential energy- of a bobbin through 

 which a current is flowing in the case of winding in 

 place. A bobbin is placed in a magnetic field and a 

 wire, carrying an electric current, is wound on this. 

 No induced E.M.F. is produced, and several theo- 

 retical deductions based on this fact are given. — E. 

 Colardeau : Method for the exact localisation of pro- 

 jectiles in wounded persons by the radiographic 

 method. The method detailed permits the exact 

 localisation of the projectile within five minutes of the 

 measurement of the photographic plates. — Victoriano 

 F. Ascarza : The total eclipse of the sun of August 21, 

 19 14, observed by the Spanish expedition at Theodosia 

 (Crimea). Observations were possible of the second 

 and third contacts and the total phase, but clouds 

 somewhat interfered with the work. Photographs 

 were taken with two spectrographs, one fitted with a 

 Rowland grating, the other with a prism, special 

 attention being given to the infra-red region (see 

 p. 432). — P. Carrasco : Physical observations made at 

 Theodosia during the total eclipse of the sun of 

 August 21, 1914. — M. Fournier : General conditions of 

 aptitude at high velocities of a hull in navigation.— J. 

 Bougault : Indene-dicarboxylic and hydrindenedicarb- 

 oxylic acids. A study of the condensation of benzyl- 

 oxalacetic ester with sulphuric acid. The reaction is 

 not analogous with the condensation of the lower 

 homologue, phenyloxalacetic ester; the ester of a new 

 indene-dicarboxvlic acid being formed : 



C«H,.< ^C.C02.C,H, 



\-C=^C02CoH5 



Proofs of this constitution are given. — Rene Regamey : 

 Cancer in plants. Proofs are given of the existence 

 in plants of a cancerous disease differing from Smith's 

 crown gall, spontaneous in the oak, and inoculable into 

 other plants. It is produced by a bacterium capable of 

 isolation and cultivation in artificial culture media. 

 The parasite is intracellular in the tumours. — P. Camot 

 and B. Weill-Halle : Biliculture in typhoid fever. Two 

 alternative methods of obtaining bile from the patient 

 are described. The cultivation of the typhoid bacilli 

 present in the bile is easy, pure cultures being readily 

 obtainable. The course of the disease can be followed, 

 and the method is especially valuable in tracing the 

 persistence of infection in convalescents and tvphoid 

 carriers. ^ — Paul Godin : a premonitory sign of pul- 

 monary tuberculosis. — F. Bordas and 5l. Brocq : Water 

 supply to armies in the field. It is accepted as funda- 

 mental that all water drunk should be previouslv 

 boiled, and the most practical way of ensuring this 

 is to insist that weak tea should be the ordinary drink. 

 For an army of 1,000,000 men, drinking one litre 

 every twenty-four hours, this implies a daily consump- 

 tion of 15,000 kilograms of tea. The problems of 

 making and distributing the tea at the front are dis- 

 cussed. The same boilers can supply not only water 

 for drinking but warm and sterilised water for the 

 treatment of the wounded. — L. G. Senrat : Precocious 

 copulation in Oxyuris. — A. Sartory and Ph. Lasseur : 

 Contribution to the study of a new pathogenic Oospora 

 {Oospora bronchialis). This new organism was 

 isolated from a case in which the most prominent 



