NO. 10 MOLLUSKS BARTSCH AND REHDER O, 



outer lip is brown variegated at the edge with light spots, which coin- 

 cide with the external light areas. There is a broad light-spotted zone 

 on the inside of the basal lip and a light spot at the base of the 

 columella. Nuclear whorls 2, too eroded to show sculpture. Post- 

 nuclear whorls strongly rounded, marked by 4 strong spiral keels, of 

 which the first is a little below the summit and the fourth at the 

 periphery, the other 2 dividing the whorls into equal spaces. These 

 keels are feebly tuberculated. Of these tubercles, 12 are present upon 

 the last whorl. In addition to this the entire surface of the whorls is 

 marked by fine equal and equally closely spaced spiral threads, 47 of 

 which are present between the summit and the periphery on the last 

 whorl. Suture moderately impressed. Periphery strongly keeled. 

 Base short, moderately convex, openly umbilicated and marked by 3 

 strong spiral keels that divide it into 4 equal areas, the fourth consti- 

 tuting the umbilicus. The 2 posterior keels are broad and rounded ; 

 the third, which borders the umbilicus, is sharp and more elevated. 

 The entire base is also marked by spiral threads, of which about 35 

 are present between the periphery and the umbilical keel. On the base 

 the incremental lines are a little more strongly developed than on the 

 spire and furnish in combination with the spiral threads a suggestion 

 of a reticulated pattern. The umbilical wall is marked by lines of 

 growth only. Aperture broadly ovate ; outer lip very strongly arched, 

 thin at the edge, posterior half of columella straight, flattened, and 

 decidedly expanded and flattened on the outer half. The parietal wall 

 is covered by a thin callus. 



The type, U.S.N.M. no. 472575, has 4.5 whorls and measures: 

 Length, 3.2 mm. ; greater diameter, 3.0 mm. It was collected in a tide 

 pool in Sulivan Bay, James Island, Galapagos. 



LITTORINA SCHMITTI, n. sp. 



Plate 2, fig. 4 



Shell broadly ovate with sharply pointed apex. The ground color is 

 blackish chestnut with narrow spiral lines of white marking the 

 grooves and more or less zigzag axial lines of white. On the base 

 the white spiral lines are also present and white axial lines produce 

 a checkerboard pattern. The outer edge of the columella is bright 

 chestnut brown, a suffusion of which covers the parietal wall. The 

 deep portion of the posterior half of the columella and the deep callus 

 on the anterior half of the parietal wall are porcelain white with faint 

 chestnut suffusion at the edge. The inside of the outer lip is marked 

 by alternate spiral zones of dark chestnut brown separated by whitish 



