LKl'KTKLLA. 



75 



P. compressum Jeffr., P. Z. S. 1882, p. (574, t. 50, f. 8. 

 P. ELEGANS Verrill. Unfigured. 



Shell small, very thin and fragile, translucent bluish-white, rather 

 depressed, elongated-elliptical with the recurved apex situated at 

 about the posterior third. The nuclear whorl is very minute, smooth 

 glassy, compressed, strongly involute and turned a little to the left, 

 forming a complete whorl, visible in a side view. The whole surface, 

 under the microscope, has the appearance of a very fine shagreen. 

 This is produced by very minute, short, wavy, raised lines, which are 

 mostly arranged in zigzag or in herring-bone style ; in some parts 

 the two sets of lines, running obliquely, cross each other at nearly 

 right angles; on other portions one or both sets are replaced by 

 minute punctations, or granulations. This sculpture is visible only 

 under a strong lens or with the compound microscope. The internal 

 lamina or septum is narrow, crescent-shaped, situated behind and 

 some little distance below the extreme apex, and not forming an 

 elongated channel ; it is distinctly visible from the outside, owing to 

 the translucency of the shell. ( Verrill.) 



Length 3-5, breadth 2-5, alt. 1 mill. 



Off Chesapeake Bay, 1395 fms. 



P. elegans Verrill, Trans. Conn. Acad, vi, p. 205. 



The animal has a short, broad ovate foot, subtruncate in front, 

 with the edge frilled. Frontal disk rather large, broad semicircular 

 or crescent-shaped, with the angles extending back in a large obtuse 

 lobe on each side. Buccal area semicircular ; mouth surrounded 

 with four convex elevations, one before and one behind it, and one 

 on each side. Tentacles slender, tapering, acute. Eyes apparently 

 wanting. No cirri on mantle. ( Verrill.) 



Subfamily Lepetellin^. Dall. 



Genus LEPETELLA Verrill, 1880. 



Lepetella Verrill, Amer. Journ. of Science, 3d Ser., xx, p. 396, 

 Nov., 1880 ; Proc. U. S. Nat. Mus. iii, p. 375, Jan., 1881.— Dall, 

 Proc. U. S. Nat. Mus. iv, p. 408, 1882 ; Blake Gastrop., p. 413. 



The animal has eyes. There are seven rows of teeth, the dental 

 formula being 2-1-1-1-2 (pi. 39, fig. 17). Soft parts otherwise as in 

 Lepeta. The embryonic shell is spiral (pi. 39, fig. 19.) 

 L. TUBicoLA Verrill & Smith. PI. 39, figs. 17, 18, 19. 



Shell thin, white, smooth, conical with the apex acute and nearly 

 central; aperture broad elliptical, oblong or subcircular, usually 



