182 DRILL! A. 



suture, usually constricted or almost closed at the edge of the 

 lip, but broadly rounded at the extremity. Length, 19'5 mill. 

 Martha's Vineyard, 94 to 146 fms. ; 



off Delaware, Bay, 104 fms. 



Animal and operculum not observed ; the generic position is 

 therefore very uncertain. It is described simply as a Pleu- 

 rofcoma. 



Unfigured Species. 

 D. PYRRHA, Watson. (Related to lanceolata, but more stumpy.) 



Japan. 

 D. STERRHA, Watson. N. Australia. 



B. Pusionellseformes. 



These shells are very like Pusionella in form, but differ in the 

 surface and in possessing the normal operculum of Pleurotoma ; 

 they differ also from the typical Drillise in wanting the callus 

 deposit on the upper portion of the labium. Any one who is 

 fond of minute divisions of the genera has here a chance to 

 distinguish himself by instituting a new subgenus. 



D. INERMIS, Hinds. PI. 12, figs. 43, 40 ; PL 32, fig. 42. 



Pinkish ash-colored under a light olivaceous epidermis, the 

 lines of growth, which are sometimes rib-like, oblique and angu- 

 lated at the periphery and lighter-colored, so that the interspaces 

 appear like angulated lines of chestnut or reddish narrow stripes ; 

 whole surface covered by close revolving incised lines. 



L. 38, diam. 13 mill. 



Southern California, L. California. 



D. penicillata, Carpenter (fig. 40), described from beach-worn 

 specimens, ha\ing the same general form as the above, as well 

 as its peculiar coloring, was supposed to differ principally in 

 having stronger and fewer plications. I can find no good char- 

 acters by which to distinguish it. The shell which Weinkaulf 

 figures for D. inermis is not that species. 



D. INCISA, Carpenter. PI. 12, fig. 41. 



Shell in general form like the preceding species, but smaller, 

 the whorls somewhat more rounded ; cinereous, with reddish 

 chestnut revolving lines. L. 1-13, diam. -4 in. PugeCs Sound. 





