The district of Cambridge 121 



and seems to have been imported, though it is perhaps 

 indigenous in the county. White examples of Pyramidula 

 rotundata, a common form in the neighbourhood, are found in 

 the Garden. As is usual in such a locality, certain foreign 

 species, introduced in packets of plants or seeds, have found a 

 home in our Garden, the cases so far observed being two of the 

 Stenogyridae, Opeas goodalli and 0. urichi from the West 

 Indies, and Physa acuta from the Continent. 



In gardens in Cambridge and in the immediate neigh- 

 bourhood many of the commoner species are easily met 

 with. Limax maximus has been recorded in cellars and hot- 

 houses within the town, while L. flavus is frequent in cellars 

 and damp lands. Milax sowerbyi and M. gagates have been 

 found in one or two gardens, and the latter also by the railway 

 bridge under Hills Road. Arion hortensis is also abundant. 

 In gardens on the Huntingdon Road side of the town Arion 

 ater and Helix aspersa are destructively common, and after 

 showers gravel walks and the side path up to Howes Close 

 may be covered with Hygromia rufescens. Helicella caperata 

 is frequent among scattered straw, and H. cantiana is quite 

 common in the neighbourhood. H. itala is more local near 

 Cambridge, but it occurs in places, though apparently not very 

 numerously. Helix nemoralis is a common form in hedgerows, 

 H. hortensis occurring more locally but in fair abundance in 

 similar situations. The former of these two is inclined to 

 follow the course of the river. Ena obscura is also fairly 

 common. 



Madingley Wood is a good hunting ground and therein 

 have been obtained Vitrea excavata, Punctum pygmaeum, 

 Acanthinula aculeata (the only record for the county and first 

 found by the Rev. A. H. Cooke in 1876) and Clausilia laminata. 

 Caecilioides acicula has been collected by Mr Cooke from fields 

 near Co ton to the west of Madingley and also from an Anglo- 

 Saxon burial ground on the site of Girton College. 



Passing to the south-west of the above places, the woods 

 in the neighbourhood of Grantchester are a locality for 



