'Geological Papers. 179 



5. Phacoides acutilineatus Conrad. Plate I, fig. 5; times, one-half. 



Lucina acutilineata Con., Wilkes's Expl. Exped., vol. X, p. 725, pi. XVII, 

 fig. 2, 1849. 



Cyclas acutilineata Con., Jour. Conch., 1865, p. 153. 



Lucina borealis (not of Linne's Syst. Nat. Edition XII, p. 1413) ; of Carpen- 

 ter, Brit. Assn. Kept., 1863, p. 643. 



Pectunculus patulus Con., Jour. Conch,, 1865, p. 153 (not Wilkes's Expl. 

 Exped., p. 726, pi. XVIII, fig. 9). 



Lucina tertica Con. (fide Gabb, Pal. Cal., vol. II, p. 100, 1869). 



Lucina borealis of Cooper, 7th Ann. Rept. Cal. St. Min., 1888, p. 246. 



Lucina acutilineata Con., Arnold, Mem. Cal. Acad. Sci., vol. Ill, pp. 131- 

 132. 



Phacoides acutilineatus Con., Arnold, Geol. Soc. Amer., vol. 17, pp. 463- 

 464 (mentioned in list only). 



Arnold's description:^^ "Shell large, orbicular, only slightly con- 

 vex, rather tjiin; umbones depressed, central; surface ornamented 

 by numerous equal, equidistant, sharp, raised, concentric lines; in- 

 terspaces show lines of growth; lunule small, but deeply impressed 

 and distinct; two sharp cardinal teeth in each valve; lateral teeth 

 nearly obsolete; anterior muscle-impression much elongated." 



Dimensions of largest specimen obtained: Lat., 70; alt., 60; 

 diam., 26. 



This species is very common in the Oligocene-Miocene strata of 

 the region along the Strait of Juan de 'Fuca; the specimen here 

 figured was obtained at East Clallam. 



Living: Catalina Island (Cooper) ; Santa Barbara channel (Car- 

 penter); Puget Sound (Arnold). 



Pleistocene: Santa Barbara to San Diego, Cal. (Cooper); San 

 Pedro, Santa Barbara, San Diego (Arnold). 



Pliocene: Stanford University (Arnold); San Fernando, San 

 Diego well, Santa Barbara, Santa Cruz, Santa Rosa, Sargent's, 

 Santa Clara county, California (Cooper). 



Miocene: Astoria and various other places in Oregon; Martinez, 

 Orestima Canon, Stanislaus county; Foxin's, Santa Barbara 

 county; Griswold's, San Benito county, California (Cooper); Point 

 Blakely, near Seattle, Wash. (Arnold). 



Oligocene-Miocene: Gettysburg, East Clallam, Wash. (Arnold; 

 Reagan); Neah Bay, Wash. (Reagan). 



5|. Phacoides nuttallii ? Conrad. 

 A fragment of a shell containing the peculiar markings of this 

 species was found in the Quillayute formation at the mouth of 

 Maxfield creek. 



37. Loc. cit. 



