ZOOLOGY 



MOLLUSCS 



Although Surrey has not been so well, or so systematically, worked 

 as some other English counties, 103 species have been recorded out of 

 the 139 known to inhabit the British Islands. 



Several more, especially slugs, will doubtless be found when 

 thorough search is made, but so far the principal records are a series 

 of -papers by Professor T. D. A. Cockerell in the Zoologist for 1885, so 

 that further and more extended observations remain to be made. 



The assemblage presents an average British facies, with the addition 

 of two or three forms of interest. Thus the occurrence of Helicella car- 

 tustana, if established, is noteworthy, since this is rather a costal species. 

 More interesting still is the discovery near Mickleham of a colony of the 

 cheese snail (Helicodonta obvoluta), and probably more may yet be met 

 with in other places along the North Downs, where it should be sought 

 for in beech woods. 



Surrey is distinctly the home of the Roman snail (Helix pomatia] , its 

 headquarters being the great escarpment of the North Downs. Its English 

 name is inappropriate, since it has been found in deposits of pre-Roman 

 age near Reigate, and was consequently not introduced by the Romans 

 as formerly supposed. Yet more unfortunate is its other trivial name of 

 'apple snail,' derived from a mistaken translation of its specific name, 

 pomatia^ which was given because in winter the animal closes the mouth 

 of its shell by secreting a chalky lid (Trm/xa) or trapdoor. 



The Royal Gardens at Kew have furnished some introduced forms, 

 such as Subulina octona from the West Indies, Physa acuta from southern 

 Europe, and Vitrea lucida, which last however may yet prove indigenous 

 in the county, since it occurs on the other side of the Thames at Isle- 

 worth. 



A. GASTROPODA 



I. PULMONATA Limax arborum, Bouch. -Chant. 



Aeriolimax agrestis (Linn.) 

 a. STYLOMMATOPHORA Barnes 



Testacella haliotidea, Drap. Nutfield Priory Amalia sowerbii (Fer.) 



in company with the next species ; Vitrina pellucida (Mttll.) 



Sutton Common Vitrea crystallina (Mull.) 



scutulum, Sby. Nutfield Priory ; Syden- lucida (Drap.) 



ham ; Croydon, etc. alliaria (Miller). Barnes Common 



Limax maximus, Linn. glabra (Brit. Auct.) 



flavw, Linn. allaria (Mull.) 



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