254 HELICID^E. 



faintly and closely striate in the line of growth, and micro- 

 scopically striate in a spiral direction : periphery rounded : 

 epidermis very thin : whorls 4 J, tumid and more prominent in 

 the middle, the last being equal to about half the shell, and 

 the first whorl and a half very small in proportion to the 

 others : spire short, very abrupt and blunt at the point : suture 

 deep : mouth small, semioval, contracted in the middle of the 

 outer edge, and furnished with teeth as follows three on 

 the pillar (the inner one of which is only a small tubercle, or 

 denticle), one on the pillar lip, and three or four (besides one 

 or two denticles) inside the outer lip and placed at some 

 distance from the opening ; the teeth are of a reddish-brown 

 colour ; the principal ones are 'strong and arched, and the 

 labial or palatal teeth extend a little way in the form of ridges 

 and are visible outside ; all of them are of an irregular shape 

 and unequal in size and length : outer lip sharp, whitish, flexu- 

 ous or constricted in the middle of the front margin, slightly 

 reflected, and strengthened by an exterior rib of nearly the 

 same colour as the rest of the shell, which is placed at some 

 little distance from the margin ; outer edge much inflected : 

 inner lip spread on the pillar and tolerably thick in adult spe- 

 cimens, so as almost to form a complete peristome : umbilicus 

 moderately open, but somewhat contracted by a blunt and 

 wrinkled crest at the base of the shell. L. 0-065. B. 0'04. 



HABITAT : Under stones and logs of wood, as well as 

 at the roots of grass, and on moss, flags, and water- 

 plants, in marshy places and at the sides of streams and 

 canals, generally throughout these isles, from the Moray 

 Firth district to Guernsey. It is also one of our upper 

 tertiary fossils. Abroad it is distributed from Sweden, 

 through the whole of Central Europe, to Portugal on the 

 west and Lugano on the east ; and Aradas and Mag- 

 giore have recorded a small variety (the Pupa pusilla of 

 Bivona) as Sicilian. 



This little mollusk carries its shell nearly straight on 

 its back, and balances it from right to left (as if it were 

 topheavy) when crawling. It inhabits elevated as well 

 as moist places. The late Dr. Johnston of Berwick in- 



