PUPISOMA. 115 



The whorls are strongly convex, joined by a very deeply 

 impressed suture; the last whorl rounded basally around the 

 open umbilicus. The aperture is rotund, slightly oblique. 

 Lip thin, the columellar margin broadly reflected, half cover- 

 ing the umbilicus in a front view, but scarcely impinging upon 

 it in a basal view. 



Length 1.56 mm., diam. 1.36 mm. ; 3% whorls. 



Length 1.6 mm., diam. 1.31 mm. ; 3% whorls. 



Galapagos Is. : Chatham Island, on a wooded hill on the 

 right side of the road from Wreck Bay to Progreso, near the 

 point where the road emerges into the grassy zone (Pinchot 

 Exped., July 4, 1929). 



This form stands close to P. macneilli Clapp, of Alabama. 

 It has a noticeably larger, more open umbilicus (compare PI. 

 16, fig. 8, galapagorum, and fig. 5, macneilli) and a higher 

 spire, and the growth wrinkles are decidedly stronger in the 

 Galapagos species. 



PuPisoMA coMicoLENSE H. B. Baker. Plate 15, fig. 6. 



Shell : small, turbinate ; epidermis light brownish with a 

 satin luster. Whorls: 4i/^, globose; suture well impressed; 

 last whorl descending. Embryonic whorls: 1% to 2, darker 

 in color than later ones; decorated with minute, raised tes- 

 sellation, which gives surface the appearance of fine-graiued 

 leather; growth-wrinkles emerge near end of second whorl. 

 Later whorls: growth-wrinkles weak and low over most of 

 shell, but slightly intensified at suture, giving latter a puck- 

 ered appearance (occasional specimens develop a few higher 

 riblets) ; entire surface vermiculate-granose, without definite 

 spirals. Umbilicus: small, rimate (about 14 times in raaj. 

 diam.). Aperture: well rounded and oblique (about 40° to 

 long axis of shell). Peristome: very weakly expanded in basal 

 and palatal regions and weakly arcuate in latter; broadly 

 reflected in columellar, so that half of umbilicus is hidden 

 (H. B. B.). 



Alt. 2.19 mm., maj. diam. 85 per cent of alt. (1.87 mm.), 

 min. diam. 80(1.76 mm.), aperture, alt. 46(1.00 mm.), diam. 

 96 (.96 mm.) ; 4l^ whorls. 



