NATURE 



[May 22, 191, 



and many other reagents ; failing to give any reaction 

 with iodine in potassium iodide solution. The endo- 

 cyst is composed of a new carbohydrate for which the 

 name Cystose is proposed. During encystation the 

 endocyst wall is digested by a powerful enzyme 

 secreted by the enclosed organism, and by this means 

 the latter is enabled to escape. The name Cystase 

 is proposed for this enzyme. — C. Shearer, W. De 

 Morgan, and H. M. Fuchs : The experimental 

 hybridisation of Echinoids. 



Cambridge. 



Philosophical Society, April 28.— Dr. Shipley, presi- 

 dent, in the chair. — A. H. Evans : Notes on additions 

 to the flora of Cambridgeshire. The author stated 

 that the combined efforts of the staff of the botany- 

 school, research students, and undergraduates had 

 resulted in a large addition to the list of species 

 given in his "Short Flora of Cambridgeshire" (Proc. 

 Camb. Phil. Soc, xvi., part 3), while others of 

 great interest had been discovered in new localities 

 or rediscovered in their former stations. Of these 

 perhaps the most interesting was the rare Prunella 

 laciniata, but lately known to have occurred in Eng- 

 land, while Mr. Moss had found with it what appeared to 

 be undoubted hybrids with P. vulgaris. — H. Hamshaw 

 Thomas : Some new and rare Jurassic plants from 

 Yorkshire. In this communication Eretmophyllum, a 

 new genus of plants allied to the Ginkgoales, is 

 described. It is founded on leaves which possess the 

 nervation, secretory tracts, and stomatal structure 

 characteristic of Ginkgo leaves, while in their linear 

 or oblanceolate shape they rather resemble those of 

 Podozamites. — C. E. Moss : Some plants new to the 

 British Isles. Rev. M. J. Le Goc : Observations on 

 Hirncola auricula-judae, Berk. (Jew's ear). The author 

 deals in his paper with the biology of Hirneola auri- 

 cula-judae, Berk., "Jew's ear," with special reference 

 to pure cultures in various media, to the fructifications 

 obtained in these cultures, and to the action of the 

 hyphae on the tissues of the host. — Prof. A. C. Dixon : 

 (1) The greatest value of a determinant the consti- 

 tuents of which are limited. (2) Expressions for the 

 remainders when 0, 9', sin fes, cos fefl are expanded in 

 ascending powers of 6. 



May 5.— Prof. Nuttall in the chair.— Prof. Nuttall : 

 Observations on ticks : (a) parthenogenesis, (b) varia- 

 tion due to nutrition. The occurrence of partheno- 

 genesis in ticks was recently observed by Aragao, in 

 Brazil, in a new species of Amblyomma (.1. agamum), 

 the males of which have not as yet been discovered. 

 Three complete generations of this tick have been 

 raised experimentally and thousands of females were 

 brought to maturity in the absence of males. This 

 constitutes the first record of parthenogenesis in ticks. 

 Prof. Nuttall described how he had succeeded in ob- 

 taining a parthenogenetic offspring from Rhipi- 

 cephalus bursa, a species (prevalent on sheep in coun- 

 tries bordering the Mediterranean) in which both sexes 

 occur in fairly equal numbers "upon the host. Larval 

 ticks issued in limited numbers from the eggs laid 

 by unfertilised females. Experiments were further 

 recorded in which it was shown that the genus Rhipi- 

 cephalus shows a considerable natural variation in 

 size, and that imperfect feeding of the tick in its 

 immature stages leads to the development of very 

 small adults which, whilst fertile, are so different 

 from the normal forms that they could readilv be 

 taken for other species. — E. Hindle : Exhibition of a 

 Chinese flea-trap. The author exhibited an ingenious 

 device for catching fleas commonly employed by the 

 natives of Setchuen, western China. The apparatus 

 consists of two pieces of bamboo one inside the other". 



NO. 2273, VOL. 91] 



The inner bamboo is coated with bird-lime to which 

 any fleas adhere, whilst the outer one merely protects 

 the sticky surface from coming into contact with bed- 

 clothes, &c, but is fenestrated in order to allow the 

 free entrance of fleas. — Prof. A. D. Imms : Exhibition 

 of living termites. The author exhibited tubes con- 

 taining living examples of the termite Archotermopsis 

 vjroughtoni, Desn. The termites were obtained bv 

 him trom the Kumam Himalayas, where they occur 

 in dead trunks of the Chir pine (Pinus longijolia) at 

 an altitude varying from about 4500 to 5800 ft. — K. R. 

 I. twin : The division of Holosticha scutellum. The 

 account of the behaviour of the micronuclei at divi- 

 sion, given by A. Gruber ("Weitere Beobachtungen an 

 vielkernigen Infusorien," Ber. Nattirf, Ges. zu Frei- 

 burg I.B., Bd. iii. (1887), pp. 57-70), is not confirmed. 

 In the period between divisions, H. scutellum possesses 

 only a small number of micronuclei of about the size 

 of the meganuclear segments, with which thev have 

 been confuted. There is therefore no necessity to 

 assume that numerous micronuclear divisions occur at 

 the fission of the infusorian. — H. B. Fantham : Sarco- 

 cvstis colii. n. -.p., a Sarcosporidian occurring in the 

 red-faced African mouse bird, Colius erythromelon. 

 The author gave an account of a new species of 

 Sarcosporicfia from a new avian host. The Sarco- 

 sporidian trophozoites (Miescher's tubes) were distri- 

 buted throughout the skeletal musculature, being more 

 concentrated in some areas than in others. Thev 

 occurred also in the heart muscle, and were scattered 

 in the pericardium, peritoneum, and in the intestinal 

 mesentery. — J. T. Saunders : Note on the food of fresh- 

 water fish. The food of fish varies considerably, 

 manv different things being taken by one species as an 

 article of diet. But a single fish does not eat indis- 

 criminatelv everything that it comes across; on the 

 contrary, its meals are found usually to consist of one 

 kind of food only. A mixture of food is not often 

 found in the stomach, and this will only occur when 

 the fish is very hungry or under artificial conditions, 

 such as obtain in a laboratory aquarium. The food 

 also varies according to locality, even in ponds which 

 are separated from each other by only a few yards ; the 

 food in the stomachs of fish taken from these ponds 

 may be quite different. This variation affects equally 

 all the individuals that live in the same pond ; under 

 the same conditions thev will all feed on the same 

 food. 



Paris. 

 Academy of Sciences, May 13.— M. F. Guyon in the 

 chair. — Paul Appell : The polynomials V w ., of Hermite 

 and their analogues connected with spherical functions 

 in space of any number of dimensions. — Armand 

 Gautier and P. Clausmann ; Fluorine in the animal 

 organism. Skeleton, cartilages, tendons. Determina- 

 tions of amounts of fluorine in bones and teeth, 

 cartilage, and tendons of mammals and fish. Fluorine 

 has been found in all the organs examined, but the 

 proportions vary widely. Fluorine is localised in a 

 definite manner in the organism; it accompanies the 

 phosphates of the alkaline earths and increases with 

 them. — Paul Sabatier and M. Murat : The preparation 

 of several die Vf/ohexylbutanes. Description of the 

 preparation and properties of five out of the nine 

 possible isomeric dicycZohexylbutanes. — L. de Launay : 

 Some broken-up rocks of the Central Plateau 

 (France'). — M. de Forcrand : Trouton's law. The rela- 

 tion L/T = constant (about 22) is known not to hold in 

 many cases, the value of L/T varying from 4-5 for 

 helium to 027 for cooper. Nernst has suggested 

 L/T = q; log T — 0007 T. This eives a closer approxi- 

 mation to experiment, but is still unsatisfactory. The 

 author further modifies this formula to 



I. T = io-i log T — 1-5 — 0-009 T + 0-0000826 T 2 . 



