March 9, 191 1] 



NATURE 



67 



1910 in the various dredgings and shore collectings made 

 in the Clew Bay area. The list includes 246 species, and 

 of these no fewer than 133 were taken in a single haul of 

 the dredge. Amongst the species enumerated are two 

 nudibranchs, here for the first time recorded as Irish, 

 Thecacera pennigera and Actaeonia cocksii. New records 

 are also given for many rare species, the most interesting 

 'being Circulus striatus {Trochus duminyi), which was 

 twice dredged in the bay. — ^J. N. Halbert : Water mites. 

 .At least four species previously unknown to science, and 

 ten others new to the British Islands, are recorded. — 

 H. Wallis Kevtr : False scorpions. — James Wilson : Agri- 

 Jculture and its history. The initial purpose of this paper 

 iiis to determine the approximate dates at which agricultural 

 Iplants and animals, not native to the island, might have 

 been introduced. To do this, it is necessary to consider 

 the history of agriculture first of all in Ireland, and then 

 in Great Britain and the neighbouring Continent, in order 

 to trace the immigration of their plants and animals west- 

 wards. The paper becomes, therefore, a concise historical 

 note on British and Irish agriculture, with special regard 

 to such data as bear upon its initial purpose. — 'N. Colgran : 

 Irish names of animals and plants. The writer has 

 collected on Clare Island and about Clew Bay current 

 Gaelic names for about 120 species of native plants and 

 animals. The dialectic variants found in use in other 

 parts of Ireland are appended to those collected in the 

 Clew Bay area, and supplementary notes are added on the 

 folk-lore found in association with certain of the animals 

 and plants referred to. 



Paris. 



Academy of Sciences, February 20.— M. Armand Gautier 

 In the chair. — J. Carpentier : Remarks on a modified 

 pattern of the spherometer due to M. Nugues. — M. Eugene 

 Tisserand was elected a member of the section of free 

 academicians, in the place of the late M. J. Tannery. — 

 Carl Stttrmer : The structure of the solar corona. 

 Calculations have been made for a series of trajectories of 

 electrified corpuscles, emanating normally from the solar 

 surface, and assuming that the magnetic field of the sun 

 is identical with that of an elementary magnet placed at 

 the centre with its axis along the axis of rotation. The 

 results of these calculations are shown graphically, and 

 compared with the form of the corona at the time of 

 minimum sun-spot frequency. — Maurice Gevrey : Partial 

 differential equations of the parabolic type. — A. Buhl : 

 The geometrical application of the formula of Stokes. — 

 Ed. Sarasin and Th. Tommasina : The action of slight 

 elevations of temperature on induced radio-activity. From 

 the experiments described, it is concluded that even small 

 elevations of temperature act on metals which have been 

 rendered radio-active, causing an immediate and temporary 

 increase in their loss of activity. — F. Leprince-Ring^uet : 

 The law of transmission of heat between a fluid in motion 

 and a metallic surface. — Paul Lebeau : Uranyl nitrate and 

 the nature of its ethereal solution. The uranyl salt forms 

 a compound with the ether used for its solution, and there 

 is a slight heat evolution. This compound can be crystal- 

 lised out by cooling the solution with a mixture of solid 

 carbon dioxide and acetone. — V. Auger and M. Gabillon : 

 A new method for the estimation of sulphuric acid and 

 sulphates. The sulphate is distilled with a mixture of 

 potassium iodide, phosphoric, pyrophosphoric, and phos- 

 phorous acids. The sulphur is given off quantitatively in 

 the form of sulphuretted hydrogen, the latter being 

 absorbed and estimated in the usual manner. The method 

 fails with barium sulphate. — G. Darzens : Condensation 

 of^ halogen derivatives with )3^-dimethylglycidic ester. 

 Dimethylglycidic ester, treated with zinc and an alkyl 

 iodide, gives substituted lactic acids of the general formula 

 Me3.CH.CR(OH).CO,H, and from these, by dehydration, 

 a series of unsaturated acids can be obtained. — E. E. Blaise 

 and L. Picard : The action of the chlorides of the 

 o-alkoxylacids on the mixed organo-derivatives of zinc. — 

 A. Guilliermond : The reproduction of Debaryomyces 

 globosus and on sortie phenomena of retrogradation of 

 sexuality observed in yeasts. These yeasts form one of the 

 'best examples known of a group in the course of evolution 

 tow, lids parthenogenesis. — Mile. G. Promsy : The influ- 

 e)K<' of acidity on germination.— M. Mazd : The excretion 



NO. 2m8, VOL. 86] 



of mineral and organic substances by roots and stomata. — 

 R. Legrendre and H. Pieron : Experimental contribution 

 to the physiology of sleep. The authors' experiments lead 

 them to the conclusion that there exists in the cerebral 

 plasma, blood, and especially in the cephalo-rachidian fluid 

 of dogs suffering from insomnia, a substance possessing a 

 hypnotoxic property. This disappears when heated t» 

 65° C, and causes an overpowering demand for sleep. — 

 M. Piettre : Muscular autolysis of pathological origin. — 

 Paul Hallez : A non-parasitic Bdelloura of the .'\ntarctic 

 seas. — Jean FfTront : The Bulgarian ferment. A com- 

 parison of total and volatile acids produced by the action 

 of seven Bulgarian ferments of different origin shows that 

 the bacterium isolated by Bertrand is clearly differentiated 

 from the rest. This ferment produces more total acid and 

 less volatile acids than any of the others. — H. Bierry : The 

 digestive ferments of manninotriose and its derivatives. — 

 J. L. Dantan : Fecondation in Paracentrotus lividus and 

 Psammechinus miliaris. — Raphael Dubois : The disease 

 affecting crayfish in the lake of Nantua. The malady is 

 shown to have been caused by a yeast, Rhabdomyces 

 Duboisii. — ^Jules Amar : The expenditure of energy in 

 walking. The energy expenditure depends on several fac- 

 tors, speed, rhythm, displacement of the centre of gravity, 

 oscillations of the body, &c., and follows no simple law. 

 The effect of carrying a load has been studied, and also 

 the most economical speed for walking. — L^n Bertrand : 

 The prolongation of the North Pyrenees sheets in the 

 western Pyrenees. 



February 27th. — M. Armand Gautier in the chair. — A. 

 Chauveau : The phenomena of visual inhibition which 

 may accompany the re-association of the two retinal images 

 dissociated by the prisms of the stereoscope. Some experi- 

 ments on stereoscopic vision with most interesting results 

 are described in detail. The inhibiting action of one eye 

 on the other is most strikingly shown in one experiment. 

 When the left eye is cut off by a screen all the details of 

 the figure are clearly seen with the right eye ; on remov- 

 ing the screen all the details of the figure disappear. — A. 

 Laveran and A. Thiroux : The identification of the patho- 

 genic trypanosomes. An examination of the method pro- 

 posed by Levaditi and Mutermilch, and based on the attach- 

 ment of the trypanosomes to leucocytes. It has been found 

 that although the method yields useful indications, it 

 cannot be relied upon for an absolute diagnosis. — E. L. 

 Bouvier : Observations in the Pycnogonomorphs and prin- 

 cipally on Pentapycnon Geayi. — ^Paul Sabatier and A. 

 Maiihe : Direct esterification and saponification by cata- 

 lysis (see p. 54). — Jean Cbazy : The determination of 

 uniform functions in the neighbourhood of points where 

 they cut. — S. Bernstein : The approximation of continued 

 functions by polynomials. — C. Cailler : The linear penta- 

 series of solid bodies. — M. d'Ocagrne : The nomographic 

 determination of the path pursued by a ship in the course 

 of varied movement. — M. Bertin : Observations on the pre- 

 ceding note. — Jean Becquerel : The duration of the phos- 

 phorescence of the uranyl salts. The duration of the phos- 

 phorescent emission is independent of the temperature (down 

 to —193° C.) for uranyl sulphate and nitrate, whilst uranyl 

 acetate, tartrate, oxalate, and other organic salts follow the 

 ordinary rule, and the phosphorescence is of longer duration 

 at the lower temperatures.— Henri Abraham : Relays and 

 electric servo-motors. — M. Ferrid : The measurement of 

 the lengths of Hertzian waves. Various tj-pes of wave 

 meters are indicated and full particulars given of the 

 method of calibration of one of them. — L. Oay : Mixtures 

 of acetic acid with normal liquids. — Eugene Fouard : A 

 practical method for the preparation of semi-permeable 

 membranes applicable to the measurement of molecular 

 weights. The method is based on the use of a collodion 

 membrane, prepared according to the description of E. 

 Roux and Salimbeni ; this is permeable to a true solution 

 but impermeable to the ultra-microscopic particles of a 

 colloid. If such a collodion tube containing a tannic acid 

 solution is placed in a gelatine solution, the membrane is 

 modified in such a manner that whilst remaining freely 

 permeable to water, it becomes impermeable to substances 

 such as sugar in solution, and thus fulfils the condition of 

 a semi-permeable membrane. Such a cell can be used to 

 prove that two solutions are isotonic with . much cfreater 

 accuracy than is obtained bv tlie method of dc Vries. — 



