FREE INSTITUTE OF SCIENCE 



709 



TERTIARY FAUNA OK FLORIDA 



Bowlder clay of Comox, Vancouver Island, Newcombe; Pleistocene of 

 San Pedro, Dall and Stearns ; of San Diego, California, at Pacific Beach, 

 Humlin. 



Smaller than P. islandicus ; ribs small, obscurely fasciculated, dichoto- 

 mous, and imbricated on both valves. Living from the Aleutian Islands south- 

 ward to Lower California. 



Pecten hericeus var. Hindsii Carpenter. 

 I'cctcn (? var.) Hindsii Cpr. , Suppl. Rep. Brit. Assoc., p. 645, 1863. 



Pleistocene of Sucia Island, Fuca Strait, Newcombe ; recent from Bering 

 Sea to Monterey, California. 



Ribs on the right valve smooth, not fasciculated, sometimes wide, flattish, 

 usually dichotomous; left valve as in var. iiavairhns. The typical specimens 

 seem remarkably distinct from navarchus, but in a large series intergradation 

 is obvious. 



Pecten hericeus var. strategus Dall. 



Pleistocene of Alaska and recent at Unalashka ; Dall. 



The fasciculi of the left valve, to the number of five to seven, with the 

 riblets coalescent, forming large, smooth-backed, turgid ribs, with smaller 

 imbricate intercalary threads. The large ribs sometimes break up suddenly 

 into the usual small riblets near the base. The recent specimens are bright 

 scarlet. 



Pecten (Chlamys) latiauritus Conrad. 



/'rA 1 // latitiHrilns Conrad, Juurn. Acad. Nat. Sci. Phila., vii., p. 238, pi. 18, fig. 9, 1838. 

 /'< -i-tt-ii /uniia Phil., 1844 i /'. iiti'solimeris Sowerby, 1847. 

 /<</<// tiimhczcnsis Orbigny, 1847, + P. aspsrsits Sby., 1843, non Lam., 1819, + P. 



Soiot'rliii Reeve, 1852 (non Guilding), is very closely related. 



Pleistocene of San Pedro Hill and San Diego at Coronado Beach ; very 

 abundant. Also living. 



Hinge-line wide; the ears acutely pointed above; ribs distinct, squarish, 

 often mesially grooved ; shell wide. This is the type, which varies widely. 



Pecten latiauritus var. monotimeris Conrad. 

 /'. Hiiiiic/iiiti-ri.i Conrad, />/>. fit., p. 238, pi. 18, fig. 10, 1838. 



Shell more oblique, inflated, and markedly shorter, with smaller ears. 

 Found with the last, with which many specimens intergrade. 



