ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 523 



consists of several vascular diverticula of the oviduct. They serve for 

 the storage of spermatozoa, which fertilise the ova as these pass out. 



In Octopus vulgaris, as others have observed, there is a keen combat 

 between male and female prior to the discharge of the hectocotylus arm 

 into the mantle-cavity of the female. Even in Sepia, where there is no 

 hectocotylisation, there is nuptial combat. 



y. Gastropoda. 



Habits of Solenogastres.* — H. Heath gives some notes on these. 

 Their habitat is on the sea bottom between 15 and 1200 fathoms, and 

 they appear fairly common and widely distributed. Upwards of fifty 

 species are known, chiefly from the waters north and south of Europe 

 and the East Indian Archipelago. They constitute the two families 

 Chgetodermatidas and Neomenidse. The latter rarely burrow in the 

 mud, but crawl on hydroid colonies or alcyonarian corals, and occa- 

 sionally on plants and some species of actinians. They are probably 

 predatory rather than commensals or parasites, though one species of 

 the genus Neomenia appears to be parasitic. It was found closely 

 wrapped about a polyp of Epizoanthus, or some closely related genus, 

 and subsequent examination showed that its proboscis had penetrated 

 the body wall of its host and had removed some of the internal struc- 

 tures, whose remains were present in abundance in the stomach. In 

 this species well developed ventral salivary glands opened at the free 

 end of the fully extended proboscis, and in the absence of a radula their 

 secretion probably exercised a solvent action on the prey. Species of 

 Chcctoderma, found abundant in mud at 300 fathoms, proved to be 

 active burrowers. This was accomplished almost entirely by movements 

 of the prothorax, similar to those of the front end of an earthworm. 



Habits of the Cellar-Slug. -j- — Karl Kiinkel has made numerous 

 observations and experiments in regard to Limax variegatus, the cellar- 

 slug, which show that its habits are strictly determined in relation to its 

 great demands for water and the correlated rapid drying of its body. 



Spermatogenesis in Enteroxenos Ostergreni.J — K. Bonnevie gives 

 a detailed account of the development of the sperm in this gastropod. 

 The leading features are the same as are found in other gastropods and 

 in Vertebrates, but certain differences in details from Paludina and 

 others are considered. 



5. Lamellibranchiata. 



Adductor Muscles of Bivalves.§ — F. Marceau has studied the two 

 portions of the adductor muscles in Lamellibranchs. These muscles 

 have two functions — that of rapidly closing the valves and that of keep- 

 ing them closed against the elasticity of the ligament. Their component 

 parts are structurally adapted to these two functions. In the oyster, for 

 instance, the rapid closure of the valves is wholly due to the contraction 

 of the " vitreous " muscle, while the " nacreous " muscle has solely the 



* Zool. Anzeig., xxvii. (1904) pp. 457-61. f Tom, cit., pp. 571-8. 



% Biol. Centralbl., xxiv. (1904) pp. 267-74, 306-10. 

 § Comptes Kendus, cxxxviii. (1904) pp. 1343-5. 



2 O 2 



