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OBSERVATIONS ON SOME BRITISH LAND AND 

 FRESHWATER SHELLS. 



(The Presidential Address read at the Annual Meeting, Oct. 21st, 1S99). 



By LIONEL E. ADAMS, B.A. 



Considering the able and interesting resumes of different aspects of 

 our science which have in recent years been given by past Presidents 

 of this society I have not thought it needful to attempt anything in 

 this direction, while the complete Annual Report of the Council leaves 

 me nothing to say regarding the Society's affairs : I have therefore 

 ventured to lay before you a few of my own personal observations on 

 some of our less known mollusks, instead of following the usual lines. 



In the following notes I have called attention to slight inaccuracies 

 in the works of some of the great conchological authorities, and I trust 

 that by making these corrections I shall not appear to disparage those 

 earlier workers who have made the science of conchology possible. 



C/ecilioides . acicula Miiller. — Having kept several of these 

 obscure little creatures alive for some time, I think a few notes on 

 their form and habits may be interesting. 



Food. — In the minute holes and fissures in which this species lives 

 at a depth varying from a few inches to four-and-a-half feet, it is 

 difficult to say what it finds to eat. Jeffreys supposed it to live upon 

 animal matter, alleging as a reason that " in the spots where it has 

 been found living, no underground fungus or other vegetation appears 

 to exist, and the form of the shell would induce a belief that this 

 snail is not only zoophagous but predaceous. The shells of all true 

 Glandina, which are carnivorous, have the same kind of notch or 

 truncature at the base as the present species of Achatina." Now, in 

 the Northants locality there is a certain amount of vegetation for 

 them to feed on — in fact many of the fissures are made by long 

 fibrous roots which penetrate often to a depth of three feet. Often, 

 too, the shells are found in worm-holes which extend to a like depth, 

 but whether they feed on the roots or upon decayed worms, beetles, 

 etc., I am unable to say. I offered my captives a variety of food, 

 and on one occasion I distinctly saw one browsing on the surface of 

 a young cabbage leaf; they were fond of crawling among damp moss, 

 but I could not see whether they fed upon it. I also provided them 

 with raw beef, worms living and dead, and leg of mouse, and placed 

 them round the meat, but they would always crawl away into the 

 moss. Nilsson has no doubt that they feed on the " tendrils and sap 

 of the roots of grasses," and I fancy he is correct. It is possible, but I 

 think it hardly probable, that they habitually come to the surface and 

 feed at night. 



