71 



966 Patula horni Gabb. 



Arivapa and San Pedro Valleys, Arizona — Honduras? 



967 Patula idahoensis Newcomb. 

 Idaho City to Montana. 



968 Patula pauper Gould. 

 Alaska to Kamtschatka. 



969 Patula solitaria Say. 



Ohio to Columbia river, Washington. 



970 Pecten alaskensis Dall. 

 Alaska to Vancouver Island. 



971 Pecten caurinus Gould. 



Puget Sound (to Santa Barbara?) — Japan. 



972 Pecten floridus Hinds. 

 Monterey, Cal., to Lower California. 



973 Pecten hindsi Carpenter. 

 Sitka, Alaska, to Santa Cruz, Cal. 



974 Pecten islandicus Muller. 



Circumboreal — Norway — south to Connecticut — to Hakododi, 

 Japan, and Puget Sound, Washington, in Pacific. 



975 Pedicularia californica Newcomb. 

 Farallon Islands, Monterey, Cal. 



976 Penitella curvata Tryon. 

 Straits of Puca to San Pedro, Cal. 



977 Periploma discus Stearns. 

 Type locality: — San Pedro, Cal. 



Stearns, U. S. natl mus pr 13:222, t 16 f 1-2. 



978 Petaloconchus macrophragma Carpenter. 

 San Diego to Panama. 



979 Phenacarion foliolatum Gould. 

 Puget Sound to coast of Oregon. 



980 Phidiana iodinea J. G. Cooper. 

 Santa Cruz to San Diego, Cal. 



981 Pholas crispata Linne. 



Circumboreal — Arctic sea to British Isles and South Carolina 

 — North Pacific ocean to San Diego, Cal. (Or.). 

 Synonym of Zirphoea crispata. 



982 Pholas pacifica 



"Shell, oblong, beaks two-fifths of length of shell from ante- 

 rior end; anterior end of valves triangular, pointed; anterior dor- 

 sal edge of valves reflected and folded down on the umbos; lower 

 anterior margin curved, forming a large elliptic-oval gape; pos- 

 terior end of valves squarely rounded; shell dull chalky white, 

 sculptured in concentric lines, which anteriorly are laminated and 

 posteriorly become extinct; valves radiantly ribbed, which also 

 become obsolete at the posterior end; at the intersection of the 

 radiating and concentric lines the sculpture is pectinated; an 

 area below the umbos, nearly or quite destitute of sculpture, 

 which varies much in prominence in different specimens, accessory 

 plate sub-lanceolate and bent down on the beaks, anteriorly pro- 

 longed over but not covering the ante-umbonal gape; interior of 

 valves white enamelled; internal rib short, curved and flattened. 

 Largest specimen, two and six-tenths inches in length, and one 

 and five-tenths inches in height. Habitat — -Alameda, San Fran- 

 cisco bay, California, where in some places it is common in sandy 

 mud between tide marks. Numerous specimens collected by 

 Messrs. Harford, Hemphill, Drs. Kellogg and W. P. Gibbons." — 

 Robert E. C. Stearns, Conchological memoranda No. 7 (28 Ag 

 1871) Cal ac pr 5: — t 1, f 6, 6a, 6b, 6c (7 Ap 1873). 



Mrs. Williamson (U S Na mu pr 15:183), reports 'three or 

 four washed ashore with the tide" at San Pedro bay, California, 



