THE NAUTILUS. 



The specimen has been presented by Mr. Harkins to the collec- 

 tion of the American Association of Couchologists. 



c. w. j. & H. A. p. 



DESCRIPTION OF A NEW VITREA FROM PUGET SOUND. 



BY W. H. DALL. 



Vitrea Johnson! n. s. 



Shell small, pale waxen-white or translucent, of three and a half 

 whorls, rather rapidly enlarging, smooth except for delicate radial 

 lines of growth which are occasionally visible; suture distinct, 

 slightly impressed ; spire hardly elevated but not flattened ; periphery 

 rounded, base convex, im perforate, the pillar lip strongly reflected 

 close to the axis; aperture semiluuar, sharp edged, the peristome 

 hardly flexuous, the upper edge a little in advance of the lower; 

 resting stages indicated internally by one or two narrow whitish 

 streaks where the shell is slightly thickened, but which do not pro- 

 ject internally. Height of shell 1, major diam. 2, minor diam. 

 1'5 mm. 



This differs from V. indentata by the absence of the impressed radial 

 grooves and by its much smaller size for the same number of whorls; 

 from V. subrupicola Dall by its more rapidly enlarging last whorl 

 and more ample aperture in specimens of the same size. The latter 

 species has one whorl less in the same diameter, and attains*, when 

 fully developed, a much larger size, besides having a peculiarly flat- 

 tened appearance both above and below. 



V. Johnsoni was named in honor of Prof. O. B. Johnson who has 

 done so much to promote interest in the rnollusk fauna of the Puget 

 Sound region. It was collected under chips with Vitrea pugetensis 

 near Seattle by Mr. P. B. Randolph. 



It may be mentioned that the original types of V. subrupicola 

 were collected at Clinton's Cave, Utah, by Dr. Packard; while 

 much larger specimens, though with the same number of whorls, 

 were collected later at Cave City, Calaveras Co., California, by 

 Hemphill. After careful study I have found no characters except 

 size to separate these from the Utah specimens, but in view of this 

 difference the former may take the varietal name of spela-a. Neither 

 form can be confounded with V. indentata by any one who critically 

 compares good specimens. A specimen of V. subrupicola with four 



