712 SUMMARY OF CURRENT RESEARCHES RELATING TO 



called the " infundibular organ." Its structure and development have 

 more resemblance to the epithelium in the saccus vasculosus of the 

 Ichthyopsidae, to which he applied the same name, than to the tuber- 

 culum posterius, which is still somewhat problematical. He also dis- 

 cusses the shape and development of the brain-vesicle. 



INVERTEBRATA. 



Mollusca. 

 a. Cephalopoda. 



Memoir on Eledone.*— Annie Isgrove gives an account of "the 

 lesser Octopus," Eledone cirrosa, or Moschites cirrosa, discussing its occur- 

 rence, habits, food, external features, internal structure, and spawning. 

 Her work seems to us a model of what a memoir of this kind should be, 

 and it is a welcome addition to the well-known and much appreciated 

 series to which it belongs. 



y. Gastropoda. 



Hibernation of Snail. t— Marguerite Bellion finds that the hygro- 

 metric state of the atmosphere is the essential external factor in inducing 

 the hibernation of Helix pomatia ; temperature is only an accessory 

 factor. In the hibernating snail there is a decrease in weight, con- 

 siderable to begin with, then slight, and finally greater again ; an 

 appreciable dehydration in the muscular and the hepatic tissue ; a 

 diminution in the fat and glycogen ; an accumulation of lecithins in 

 the liver, the muscles, and the albumen gland ; an accumulation of 

 glucose in the liver, the pedal muscle, the albumen gland, and in the 

 blood. In the first part of the hibernation the liberation of water 

 vapour and carbon dioxide diminishes considerably. The values of the 

 respiratory quotients decrease continuously from the beginning to the 

 end of hibernation. There is an accumulation of carbon dioxide in the 

 tissues as the oxygen decreases. 



Respiration of Hibernating Snail.}— Marguerite Bellion finds that 

 the respiratory exchanges in Helix pomatia are much less intense during 

 hibernation. The amount of water vapour given off diminishes greatly 

 at the beginning of the hibernation, and then remains almost constant. 

 It is in the middle of the hibernation that there is a great decrease in 

 the amount of carbon dioxide given off. It becomes almost un- 

 detectable and remains very slight on to the end of the period. The 

 value of the respiratory quotient diminishes progressively from the 

 formation of the operculum onwards. The amount of oxygen in the in- 

 ternal gas of the animal diminishes during hibernation, reaching a 

 minimum in February, but the amount of carl >on dioxide accumulates. 



Action of Radium Rays on Ova of PhilineJ— Jan Tur exposed 

 the eggs of Fhiline aperta for 6-20 hours to a strong radioactive prepa- 

 ration, the rays passing through a thin glass plate. The segmentation 



* Liverpool Marine Biol. Comm., Memoir xviii. (1909) pp. 1-105(10 pis.). 



f C.R. Soc. Biol. Paris, lxvi. (1909) pp. 964-6. 



% Tom. cit., pp. 917-18. § Gomptes Rendus, cxlix. (1909) pp. 439-41. 



