PUPA. 245 



folds within the outer lip of adult specimens and is repeated 

 at short intervals ; these transverse plates or septa are dis- 

 tinctly visible outside the base of young shells : outer lip and 

 pillar lip light reddish-brown, much thickened and slightly 

 reflected : umbilicus small, narrow and oblique, but distinct. 

 L. 0-133. B. 0-65. 



Yar. pallida. Shell of a lighter colour, sometimes whitish. 



HABITAT : Among dead leaves and moss, and at the 

 roots of grass, in moist places throughout the northern 

 counties of England, the West of Scotland, and all 

 Ireland, as well as in Guernsey. It occurs in a sub- 

 fossil state at Copford. Its foreign range appears to 

 be limited, so far as is at present known, it having 

 only been found once in the rejectamenta of a river near 

 Toulouse (Moquin-Tandon), Cintra and the neighbour- 

 hood of Oporto (Morelet and Pring), and Algeria (More- 

 let and Dupuy). This southern distribution would seem 

 to bear out the conjecture made bythe authors of the 

 ' British Mollusca ' that the present species " is probably 

 a member of our Atlantic fauna and of Southern or 

 South-western origin ; " but at the same time its occur- 

 rence as an upper tertiary fossil, with Helix lamellata 

 and many other decidedly Northern forms, is a fact that 

 must not be overlooked in considering the geographical 

 distribution of the Mollusca. 



This is a shy little creature, although tolerably active 

 when inclined to make its appearance. It has a singular 

 habit of withdrawing slowly one of its eyes, which rolls 

 backwards like a little ball until it reaches the neck, 

 while the tentacle which supports it remains extended 

 to its full length. This I have observed being done 

 when there was no obstacle in the way. It also retracts 

 occasionally, and apparently without any reason, one of 

 its horns and not the other. It does not appear to be 

 ovoviviparous, like the next species (P. umUlicata) : at 



