EASTERN PROVINCE — INTERIOR REGION SPECIES, 335 



Head and back deep cherry-red, posterior part of foot bluish, base 

 whitish. Eye-peduucles larger towards the extremities, or remarkably 

 club-shaped ; ocular points distinct. The anterior extremity of the foot 

 is dilated and trilobate, the middle lobe minute, lateral lobes rounded. 

 Length rather greater than that of the axis of the shell. 



Of forty specimens of this shell examined with the aid of a micro- 

 scope, one had a single tooth, two had three teeth, and twenty-eight had 

 two teeth upon the transverse margin, the one nearest the center being 

 always largest and most prominent ; and all of them had the bilobate or 

 double-curved aperture and the irregular indentation upon the outer 

 whorl, near the peristome. A single specimen had three teeth upon the 

 peristome and three upon the transverse margin, making, with two 

 upon the columellar margin, eight in all. The semicircular mouth is 

 abrui^tly truncated by the last whorl, which forms a distinct and nearly 

 transverse limit. The peristome is thin and a little turned outwards; 

 its edge is often whitish, but within it is brownish and often thickened. 

 The indentation of the last whorl, terminating at the angle of the peri- 

 stome, is a prominent character. The teeth of the peristome are often 

 curved towards the center of the aperture. 



The motion of the animal when in j)rogress is rapid but awkward. 

 The proboscis, which is long and projectile, seems to be thrust forward 

 and attached and the rest of the foot drawn up to it, reminding one of 

 the motion of a caterpillar, the shell at the same time rolling from side 

 to side. The adherent forces of the animal evidently lie in the anterior 

 part of the foot. 



This is one of the more aquatic species, and is found under dead 

 leaves and sticks and on the stems of plants at the margin of rivulets 

 and ponds. 



The species has been referred to P. antivertigo, but the figure of the 

 dentition of that species given by Lehmann (Plate XIV, Fig. 52) does 

 not sustain the theory of identity. 



SPURIOUS SPECIES OF VERTIGO. 



Vertigo coniracta, Adams, Geu. Rec. Moll., is the same as Pupa contracta. 

 Vertigo decora, Adams, Geu. Rec. Moll., is the same as Pupa decora. 

 Vertigo minuta, Adams, Gen. Rec. Moll., is the same as Pupa rupicola. 

 Vertigo pentodon, Say, is the same as Pupa pentodon. 

 Vertigo rupicola, Binney, is the same as Pupa rupicola. 

 Vertigo corticaria, Binney, is the same as Pupa corticaria. 



