PEDIPES. 1? 



the West Indies, three in Europe, and one of doubtful identity 

 is referred to the United States. 



Leuconia sayii, Kuster. — Shell small, conic-ovate, shining, horn- 

 colored, striate ; spire acute, broadly conic, whirls five, 

 rather convex; aperture oblong, columella biplicate. rig. ^0. 

 Length 2h lines, diam. li. 



United States. (Kuster.) 



Auricula sayii, Kuster in Chemn. ed. 2, 12, pi. vi, f. 14, 15. 

 Leiiconia sayii, Pfeiffek, Mon. Auric. 157; Brit. Mus. 



Auric. 170.— W. G. Binney, Terr. Moll. IV, 177, pi. 



Ixxv, f. 34. 



Leuconia sayii. 



The above is Kiister's description. The figure I 

 give is a fac-simile of one of his. This is the only information 

 I have been able to obtain with regard to the species. It has 

 not been described by any other author but Pfeiffer, who merely 

 quotes the above description, not having ever seen the shell. 



Kiister's figure represents no known American shell ; there 

 exists, however, a strong resemblance between it and his figure 

 of Alexia myosotis. His original specimen may have been a 

 variety of that species. 



Pfeiffer compares the species with Melamims ivfreqiiens, Ad. 



PEDIPES, Adanson. 



Foot divided inferiorly by a transverse groove. 

 Shell subglobose, imperforate, transversely striated ; spire 

 short, obtuse ; aperture narrow ; inner lip flattened, excavated, 

 with three plaits, the posterior the largest ; outer lip posteriorly 

 sinuated, with two teeth internally ; margin acute. 



Species of Pedipes have been found at Panama, in Africa, the 

 West Indies, Madeira, and Isle of France. They are said to 

 inhabit crevices of rocks, especially those exposed to the full force 

 of the tide. The generic name was suggested by the peculiar 

 mode of progression. When the animal walks, the hind part of 

 the foot is fixed, and the fore part, which is separated from the 

 hind part by an extensible groove, is advanced, and the hind half 

 is then drawn forwards so as to touch the antei'ior half, and so 

 progression is effected by a series of little steps. This movement 



