. Bulletin of the Museum of Comparative Zoology at Harvard College. Zoology; Zoology. Fis. But one species of this genus has been described, P. pj/gmceum, Dr., hitherto known in America as Helix minutissima, Lea. A full account of its history, with all j)ublished information relat- ing to it, has been given by Mr. Bland ^'K 288. and myself in Ann. of Lye. Nat. His. of N. Y., X. 30G. The jaw is low, wide, slightly arcuate, with blunt, squarely truncated ends; it is com- J&w of P. py^wcPMrn (Morse). posed of sixteen separate i)ieces, each higher than wide, with slightly overlapping edg
. Bulletin of the Museum of Comparative Zoology at Harvard College. Zoology; Zoology. Fis. But one species of this genus has been described, P. pj/gmceum, Dr., hitherto known in America as Helix minutissima, Lea. A full account of its history, with all j)ublished information relat- ing to it, has been given by Mr. Bland ^'K 288. and myself in Ann. of Lye. Nat. His. of N. Y., X. 30G. The jaw is low, wide, slightly arcuate, with blunt, squarely truncated ends; it is com- J&w of P. py^wcPMrn (Morse). posed of sixteen separate i)ieces, each higher than wide, with slightly overlapping edges; these pieces do not run obliquely towards the middle of the jaw; there is, therefore, no appearance of an upper median triangular piece, as in Orllialicus and Liguus. The lingual membrane is long and narrow. There are 54 rows of 13—1—13 teeth each. The centrals have a base of at- tachment much longer than wide, expanded below and squarely truncated, very much narrowed above, reflected. The reflection is very small, and has, according to Morse, one single cusp, but Schacko (Malak. Bliitt., 1872, 178) describes the reflection in some European specimens as tricuspid. Laterals of same form as centrals, but with wider base of attachment in the first ones and biscuspid; outer laterals much narrower. There are no distinct marginals. All the teeth are decidedly separated. I have not examined the jaw or lingual membrane of this species, but am entirely dependent on Morse for the descriptions and figures of the American form given above. While treating of the identity of the American and Euro- pean forms in the paper referred to above, we have pointed out the differences in the jaw and membrane of the two forms, which, however, do not appear to be of specific value. Punctum pygmaeum, Drap. Shell umbilicated, subglobose, reddish horn-color, shining, marked with strong transverse strias and microscopic revolving lines, both most prominent near the umbilicus; whorls 4, convex, gradu
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