AMBER SNAILS. 61 



" After dissecting and examining many specimens 

 under a microscope, I have found that the upper jaw 

 is in S. putris divided into three teeth, one large 

 projection in the centre and two small ones, one on 

 each side ; whereas, in S. pfeifferi, there is only one 

 tooth-like projection in the centre of the jaw. I 

 have found this to be invariable in very many speci- 

 mens of both kinds that I have examined ; and the 

 fact goes far to convince me that S. putris and 

 S. pfeifferi are more distantly connected than some 

 conchologists seem to think." 



Mr. Gwyn Jeffreys, who considers elegans or 

 pfeifferi distinct from putris, has met with speci- 

 mens of the former in the neighbourhood of Ham- 

 mersmith. A third British species, oblonga, is 

 much rarer, or more correctly speaking more local, 

 being generally met with in ditches near the sea 

 coast. We know of no instance of its occurrence 

 near London, although Cooper, in the list to which 

 we have already referred, includes oblonga as found 

 by Mr. James Carter at Hammersmith. We suspect 

 that he means elegans, which is more oblong in 

 shape than putris, the only other species which he 

 included, although by another name, viz., amphibia. 



