ARNOLD — THE PALEONTOLOGY AND STRATIGKAPHY OF SAN PEDRO. 127 



This little shell is one of the unique species of this fauna. Specimens identi- 

 fied by Dr. Dall. 



One specimen from lower San Pedro series of Deadman Island, which is 

 figured, and is now in the collection of Delos Arnold. 



Living. — Santa Barbara; Samarang, China; South America (Carpenter): 

 San Pedro (Raymond). 



Pleistocene. — San Pedro (Arnold). 



Order TELEODESMACEA. 

 Superfamily ASTARTACEA. 

 . Family XVIII. , ASTARTID.E. 

 Genus Astarte Soiverby. 



Shell suborbicular, compressed, thick, smooth, or concentrically furrowed; lunule com- 

 pressed; ligament external; epidermis dark; hinge-teeth two in each valve, the anterior tooth of the 

 right valve large and thick ; anterior pedal scar distinct ; pallial line simple. 



Astarte semisulcata Leach is a characteristic species. 



Subgenus Crassinella Bayle. 

 Shell obliquely lengthened, subquadrangular. 

 Astarte ohliqua Dash, is a characteristic species. 



53. Astarte (Crassinella) branneri, sp. nov. 



Plate XVIII, Fig. 12. 



Shell small, subtrigonal, equivalve, inequilateral, convex, thick; umbo small, sharp; ante- 

 rior dorsal margin straight to anterior extremity, where it meets the arcuate ventral margin in an 

 angle ; posterior dorsal margin evenly arcuate, sloping down to rounded, posterior extremity ; surface 

 sculptured with numerous angular, concentric undulations or ridges ; lunule long, narrow, extending 

 to anterior extremity, and circumscribed by a narrow, angular ridge ; ligament external, not promi- 

 nent; two prominent cardinal teeth in right valve; one in lelt; no laterals; pallial line entire, running 

 from the middle of adductor scars ; adductor scars subequal, small. 



Dimensions. — Long. 10 mm.; alt. 8.9 mm.; diam. 5 mm. 



This species somewhat resembles Astarte compacta Cpr., but has a longer 

 lunule, finer concentric ridges, and is more bilaterally symmetrical. Specimens 

 pronounced a new species by Dr. Dall. Named in honor of Dr. John C. Branner, 

 Professor of Geology, Leland Stanford Junior University. 



Rare in the upper San Pedi'o series of San Pedro and Los Cerritos. The 

 specimen figured is the type, which is from the ujijier San Pedro series at Los 



