Clark: The San Lorenzo Series of Middle California 141 



CAEDIUM LORENZANUM Arnold 



Cardium oooperi Gabb lorenzanum Arnold, Proc. U. S. Nat. Mus., vol. 34, 



no. 1617, p. 366, pi. 33, fig. 6, 1908. 

 Cardium oooperi Gabb lorenzanum Arnold, Santa Cruz Folio, U. S. Geol. 



Surv., no. 163, p. 4, Mus. 2, fig. 17, 1909. 

 Cardium cvoperi Gabb lorenzanum Arnold, Weaver, Wash. State Geol. 



Surv., Bull. 15, p. 18, 1912. 

 Cardium lorenzoanum Arnold, Arnold and Hannibal, Proe. Amer. Pliilos. 



Soc, vol. 52, pp. 581, 588, 1913. 

 Cardium lorenzanum Arnold, Clark, Univ. Calif. Publ., Bull. Dept. Geol., 



vol. 9, no. 2, pp. 14 and 18, 1915. 

 Occurrence. — Rare in the San Ramon formation but fairly common in the 

 Kirker formation north of Mount Diablo. 



CARDIUM ef. VAQUEROSENSIS Arnold 



Cardium vaqucrosensis Arnold, Proe. U. S. Nat. Mus., vol. 34, p. 378, pi. 

 34, fig. 3, 1908. 



Cardium vaquerosensis Arnold, U. S. Geol. Surv., Polio 63, p. 4, illus. 2, 

 fig. 34, 1909. 



Cardium vaquerosensis Arnold, Smith, Proc. Calif. Acad. Sci., ser. 4, vol. 3, 



pp. 165 and 171, 1912. 

 Cardium vaquerosensis Arnold, Anderson and Martin, Proe. Calif. Acad. 



Sci., ser. 4, vol. 4, pp. 40-41, 1914. 

 Cardium vaquerosensis Arnold, Clark, Univ. Calif. Publ., Bull. Dept. GeoL 



vol. 9, no. 2, p. 14, 1915. 



The type of Cardium vaqucrosensis, as figured by Arnold, is very 

 poor; a specimen, which is here referred questionably to that species, 

 was obtained at University of California locality 1131, at the base 

 of the San Ramon formation ; this also is incomplete, and one would 

 be justified only in comparing this form with Arnold's species. 



Family Veneridae 

 Genus DOSINIA Scophield 

 DOSINIA (DOSINIDIA) MATHEWSONII Gabb 

 Plate 7, figures 1, 2, 5, 6, and 9 



Dosinia mathewsonii Gabb, Geol. Surv. Calif., Palaeontology, vol. 2, p. 57, 



pi. 15, fig. 16, 1867. 

 Dosinia mathewsonii Gabb, Merriam, Univ. Calif. Publ., Bull. Dept. Geol., 



vol. 3, no. 16, p. 378, 1904. 

 Dosinia mathewsonii Gabb, F. M. Anderson, Calif. Acad. Sci., ser. 3, vol. 2, 



pp. 186, 188. 



Dosinia mathewsonii Gabb, Arnold, U. S. Geol. Surv., Prof, paper no. 47, 

 p. 19, 1906. 



