TRANSACTIONS OF WAGNER 

 706 



TERTIARY FAUNA OF FLORIDA 



radially and the others concentrically threaded ; the left valve somewhat less 

 convex. Alt. 145, lat. 147, extreme length of hinge-line 80 mm. 



Pecten sp. San Pablo formation, Mount Diablo, Contra Costa County, 

 California, has fourteen to sixteen ribs, strong and simple, with narrower chan- 

 nelled interspaces, which, as well as the ribs in some cases, are radially striated; 

 ears subequal, somewhat impressed, with a few rather coarse radial riblets and 

 concentric striation. Alt. 127, lat. 137, hinge-line 70 mm. 



Pccteii .sp. A small species recalling P. descrti was collected near Mount 

 Diablo; it is rounded, moderately convex, with eighteen to twenty slightly 

 nodulous subequal ribs, with channelled equal interspaces crossed by fine 

 looped concentric sculpture ; the shell is like a small ceqidsulcaUis in general 

 form, with small subequal ears. Alt. 28, lat. 28, hinge-line 18 mm. 



Pecten sp. indet. The flat valve of a species, in poor condition, but re- 

 calling P. dentatus Sby., has been received from Miocene beds near San Diego. 



The following are of Pliocene age : 



Pecten (Patinopecten) expansus Dall. 

 Plate 26, Figure i. 

 Pecten expansus Dall, Proc. U. S. Nat. Mus., i., p. 14, 1878. 



Pliocene of Pacific Beach (lower horizon), near San Diego, CaHfornia ; 

 Flemphill, Dall, and Hamlin. 



Shell large, flattish, with, on the right valve, twenty-five to thirty flat 

 dichotomous ribs, which differentiate it from the other species of this group. 



Pecten (Pecten) Stearnsii Dall. 

 Pl.'Vte 26, Figure 5. 

 Pecten Stcnrnsii 'D2M, op. ctt., p. 15, 1S78. 

 Found with P. expansus. 



This is the Pliocene precursor of Pecten diegensis Dall, from wliich it 

 differs by having five or six more ribs, which, in the adult, have a conspicuous 

 median sulcus. 



Pecten laqueatiis Sby., a Japanese species, has been erroneously cited by 

 Reeve from California. 



Pecten (Pecten) Hemphillii Dall. 

 Pecten Heinp/iittii XiaW, op. cit., p. 15, 1S78. 



Janira bctta Gabb (non Conrad), Pal. Cal., ii,, pi. 16, fig. 20, 1S69; not P. hetta Sby., 

 nor /-". betlis McCoy. 



