156 JOURNAL OK CONCHOLOGY, Vai,. I5, NO. 5, JANUARY, I917. 



the food which the young will require when hatched. The majority 

 deposit their eggs in excavations which they hollow out to varying 

 depths in tlie ground at the foot of trees, under leaves, or amongst 

 grass roots, where they will receive a certain amount of warmth and 

 moisture ; whilst some are deposited underneath stones or logs. By 

 keeping Helix pomatia L. in captivity, the manner in which the bur- 

 rowing snails excavate their nidus can readily be demonstrated, and, 

 apart from the interest of watching the operation, there is every 

 chance of obtaining the hard-shelled, dull-white, globular eggs, 

 measuring 6 mm. in diameter — the largest egg produced by a British 

 snail. Some curious deviations from the usual method of depositing 

 tlie eggs occur in a few families. Cochlostyla vimdoro'ensis Brod., for 

 instance, which alone, according to Cuming, of all the arboreal snails 

 inhabiting the Philippmes, has calcareous eggs, deposits them upon a 

 leaf in parallel rows, each standing perpendicularly on end, attached 

 at the base by a glutinous substance. In others of the same family 

 the eggs are soft, and are deposited in a bag, which the parent snail 

 twists up for their reception from the leaves of the tree upon which it 

 lives. Libera fratercula Pease and its congeners, from the Society 

 and Cook's Islands, are described by Pease as remarkable for their 

 Iiabit of ovipositing into the cavernous umbilicus of the shell, which 

 is strongly constricted below so as to form a pouch-like cavity within; 

 into this the eggs to the number of from four to six, or the same 

 number of embryonic shells when hatched, are closely packed. By 

 some of the species in this genus they are still more effectively 

 retained in position by a temporary shelly plate, which partially covers 

 the umbilical opening, and is subsequently broken aw^ay or absorbed 

 by the animal to facilitate the escape of the young shells. Psenda- 

 chatina dowiiesii (Gray) and its allies, from West Africa, lay their eggs 

 in the axils of the branches of the trees upon which they live. Testa- 

 cella haliotidea Draparnaud deposits its eggs here and there in its 

 subterranean galleries, sometimes a yard or more beneath the surface. 

 H.yaliiiia is the only group, as far as I know, which seems to make 

 no sort of provision for the welfare of its eggs, which are simply 

 dropped singly here and there amongst moss or herbage, and left to 

 chance. This appears to be the normal procedure in each species, 

 though I have on one occasion taken a specimen of H. cellaria 

 (Miill.) under a log in the act of laying, with a little pile of ten eggs 

 beside it. The eggs are spherical, dull-white, calcareous, and i"5 mm. 

 in diameter. The eggs of H. Iticida (Drap.) are practically indistin- 

 guishable from those of H. cellaria (Miill.). The eggs of ^ alliaria 

 (Miller) are round, pure white, i'5 mm. in diameter; those of H. niii- 

 dula (Drap.) are spherical, opaque-white, rather glossy, and are i'5 

 mm. in diameter. Zouitoides nitidxts (Miill.) has opaque-white eggs, 



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