58 SUMMARY OF CURRENT RESEARCHES RELATING TO 



sense-corpuscles, and that there is no part which can be described as a 

 group of specialised olfactory cells. In reality, the sensory cells are 

 " mixed " and respond to shock, heat, or odour. The whole exposed 

 surface of the body is sensory, the long tentacles most so, and next the 

 smaller pair, and next the dorsal surface. Snails deprived of both pairs 

 of tentacles were able to find food placed in their vicinity ; in one case 

 a piece of ripe melon was " tracked " at a distance of 40 centimetres. 



Structure of Cryptoplax larvae formis.*— Ernst "Wettstein describes 

 the structure of this representative of the Cryptoplacidae, an interesting 

 family of Placophora, which seems likely to throw some light on the 

 affinities between Placophora and Solenogastres. 



The form is elongated, almost worm-like ; the strongly developed 

 mantle makes the foot inconspicuous ; the mantle cavity is deepest in 

 the region of the gills ; localised muscle strands are lost in the general 

 body-nmsculature,whieh like the form, means adaptation to boring ; the 

 stomach and intestine are spirally coiled ; the pericardium is reduced in 

 its most anterior portion to a narrow vesicle ; the aorta is connected by 

 looping vessels with the vena pallia! is (peculiar to Cryptoplacidai), and 

 the latter with the sinus lateralis. 



The most notable fact in regard to the nervous system is the 

 shunting of the origin of the buccal connective to the posterior portion 

 of the cerebral semicircle. A peculiarity, which only occurs elsewhere in 

 Aplacophora, is the existence of two connections of the pleurovisceral 

 strands over the hind-gut. 



The left and right kidney are directly connected by a vesicle. This 

 species agrees with C. oculatas in the dorsal position of the main canal 

 and of the reno-pericardial duct, and in the nature of the reproductive 

 organs. 



5. Lamellibranchiata. 



Anatomy of Anomia ephippium.f — Moriz Sassi, in a detailed 

 research on the heart and kidneys of Anomia ephippium, sets himself to 

 discover whether a portion of the ccelome exists with which the kidneys 

 communicate by a ciliated funnel, and if so, whether it also functions as 

 a pericardium. He finds that each kidney has the remains of such a 

 funnel communicating with a small sac-shaped remnant of the ccelome, 

 which from its position might have been originally situated round the 

 heart. 



Arthropoda. 

 a. Insecta. 



Habits and Instincts of Insects. J— J. H. Fabre has published the 

 eighth series of his delightful " Souvenirs Entomologiques." It deals 

 with rose-beetles, bean-beetles, Pentatomas and masked bugs, aphides, 

 wild bees, carrion-flies, etc. Special attention has been given to eggs, 



* Jenaische Zeifschr. Naturwiss., xxxviii. (1903) pp. 473-501 (3 pis.). 



t Arbeit. Zool. Inst. Univ. Wien, xv. (1903) p. 1-16,(1 pi-)- 



X 'Souvenirs Entomologiques (Huitieme Serie) : Etudes sur l'Instinct et les 

 Mceurs des Insectes.' Svo, Paris, 1903) p. 379. See Ann. Nat. Hist., xii. (1903) 

 pp. 637-8. 



