494 University of California Publications in Geology [Vol. 8 



N. tegula Reeve, a Recent species on this coast, develops a varix on 

 the. outer lip but in other respects it differs very radically from N. 

 pabloensis. 



Dimensions. — Type specimen : height, 16 mm. ; greatest width of 

 body whorl, 7 mm. ; height of body whorl measured just posterior to 

 outer lip, 7 mm. 



Occurrence. — From the Upper San Pablo Group, University of 

 California localities 1947 and 1948, south side of Mount Diablo Anti- 

 cline to the east of Walnut Creek, and locality 1617, San Pablo Bay 

 section about one mile east of Union Oil Works. 



HEMIFUSUS DALLI, n. sp. 

 Plate 68, figure 10 



Shell small, fusiform; spire moderate in height; apex acute; 

 sutures obscurely impressed ; whorls five, subangulate ; surface above 

 the angulation subtabulate ; surface of whorls covered by medium 

 fine, rather numerous, rounded longitudinal ribs ; on the body whorl 

 there are twelve or thirteen of these ribs, which gradually disappear 

 toward the anterior part of the whorl ; the longitudinal ribbing is 

 quite prominent on the anterior whorl of the spire but is very faint 

 on the other whorls ; surface, also, sculptured by fairly coarse, rounded, 

 spiral ribbing with interspaces slightly narrower than the ribs ; where 

 the spiral ribbing passes over the longitudinal ribbing a node is 

 formed, thus the upper part of the body whorl and the first whorl of 

 the spire are quite nodose ; outer lip sharp, thin ; inner lip smooth, not 

 incrusted ; canal short and straight, open and rather deep ; umbilicus 

 imperforate. 



Dimensions. — Length, 10 mm. ; length of body whorl, 6 mm. ; great- 

 est width of body whorl, 5 mm. 



Occurrence. — A single specimen has been found in the Upper San 

 Pablo Group on San Pablo Bay, University of California locality 1631 ; 

 associated with Cyrina calif omica Gabb, Maooma pabloensis, n. sp., 

 My a clichersoni, n. sp., Mytilus perrini, n. sp., and Bittium pabloensis, 

 n. sp. 



CHRYSODOMUS BUWALDI, n. sp. 

 Plate 68, figure 4 



Shell medium in size, fusiform ; body whorl long. Spire moderate 

 in height ; whorls regularly convex. Number of whorls five. Sutures 

 deeply impressed. Surface of whorls sculptured by coarse, broadly 



