ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 37 



parallel to the production of heat in a contracting muscle, or of electric 

 discharges in the Torpedo. Very noteworthy is the remarkable economy 

 of the illuminant ; a perfectly infinitesimal proportion of the energy 

 expended is wasted on the production of heat. 



Liver of Cuttlefishes.* — L. Cuenot finds that the liver includes, 

 apart from indifferent replacement-cells, two types : — (1) Goblet 

 safranophilous cells with fat globules (often inclosing a yellow magma 

 with crystals) ; and (2) vacuolar cells. The vacuoles and the magmas 

 are periodically ejected. The vacuolar cells are proved by experiment 

 to be excretory, and they also arrest pigments added to the food. Thus 

 the liver is an absorbing organ — the chief absorbing organ, as in other 

 Invertebrates. In the spiral caecum fats are absorbed, but nothing else. 



Octopus with Branching Arms.f — Edgar A. Smith gives a descrip- 

 tion of a Cephalopod from Japan, in which five of the eight arms branch 

 more than once, and that irregularly. Such forking appears to be of 

 rare occurrence. The species is that described as Polypus cephea Gray, 

 from a single specimen, now in the British Museum. 



New Cephalopods from the Irish Coast.! — A. L. Massy describes 

 Polypus profundkula sp. n., which appears to be very nearly allied to 

 Octopus eryasticus Fischer, particularly in the form of the hectocotylised 

 arm ; P. normani sp. n., a graceful form taken at 710 fathoms ; and 

 HelkocraucMa pfefferi g. et sp. n., a minute form with large, oval, 

 pedunculate fins attached to the end of the dorsal surface, and with an 

 extremely large siphon. The occurrence of several other forms not 

 hitherto recorded for British and Irish waters is noted. 



y. Gastropoda. 



Reproduction in Snails. § — J. Meisenheimer has made an elaborate 

 study of the bionomics of pairing in Helix pomatia. To procure 

 material he kept snails in a terrarium, and was able to witness the 

 process fifty times, and to secure many interesting photographs and pre- 

 parations. Pairing takes place in May and June, reaching its maximum 

 frequency in the first half of June. Snails in search of mates may be 

 seen to creep slowly about, feeling from side to side, with the forepart of 

 the body slightly raised, and to remain rigid for short periods in that 

 attitude. When two such snails meet, they raise themselves up so that 

 almost the whole base of the foot is apposed, only the hinder part of it 

 and the shell supporting the animal on the ground. This is the charac- 

 teristic attitude, which is maintained throughout the whole process. 

 Breathing is rapid, undulatory movements pass through the foot con- 

 tinually, mouth-papilas and horns are in a state of constant activity, and 

 the whole organism betrays signs of excitement. This preparatory stage 

 is short, and both snails sink downwards in apparent exhaustion. After 

 a pause of about half-an-hour, excitement again becomes manifest, and 

 the movements recommence. One snail usually shows more activity 



* Arch. Zool. Exper., vii. (1907) pp. 227-45 (1 fig.). 



+ Ann. Nat. Hist., cxix., (1907) pp. 407-10. 



J Tom. cit., pp. 377-84. 



§ Zool. Jahrb., xxv. (1907) pp. 461-502 (3 pis., 4 figs.). 



