Vol. V] DICKERSON— FAUNA OF THE TYPE TEJON 53 



This species differs from Glycimeris cor in having a more 

 pointed beak, in lack of hinge teeth in the central portion of 

 its hinge and in general shape. Glycimeris cor Gabb is figured 

 for comparison. (See Plate a, figure 6). 



Dimensions: — Height of type, 19mm.; length, 17mm.; con- 

 vexity, 6mm. 



Type: — No. 11051, University of California. Locality 458, 

 Tejon Quadrangle. Tejon group. West side of Grapevine 

 Creek, elevation 2050 feet, about 4>^ miles S. 6° W. of 1085 

 B, M. ; about 400 feet (stratigraphically) above Basement 

 Complex-Tejon contact. R. E. D. 536. Coll., R. E. Dickerson. 



Named in honor of Mr. John Ruckman. 



Meretrix tejonensis, new name 

 Plate 3, figures 2a and 2b 



Meretrix iivasaua Gabb, not Conrad, Gabb, W. M., Geology 

 of California, Palaeontology, vol. 1, pp. 163-164, 1864. 



Gabb's description is as follows : 



"Shell thick, oval, robust, a fourth longer than wide, very 

 inequilateral ; beaks large, strongly incurved, placed less than 

 a third of the length from the anterior end ; buccal margin 

 prominently rounded below, deeply excavated under the beaks ; 

 cardinal margin sloping very convexly towards the posterior 

 end, which is subtruncated. Surface marked by small lamel- 

 liform ribs, separated by spaces about equal to four times the 

 thickness of the ribs themselves ; the interspaces are sometimes 

 plain, sometimes striated. Inner margin plain. 



Localities : Abundant near Fort Tejon, whence it was de- 

 scribed by Mr. Conrad; also found not rarely, near Martinez, 

 and nearly everywhere in Division B. 



This is the largest species of the genus, and one of the com- 

 monest fossils in California. The figure given in the Pacific 

 Railroad Report is from a fragmentary specimen, and conveys 

 a very incorrect idea of the outline of the shell. There can be 

 no doubt of the identity of the present form with Mr. Conrad's 

 species, since I collected numerous specimens myself, at the 

 original locality; and this is the only species with the peculiar 

 surface ornamentation, mentioned by Mr. Conrad, that has 

 been found in California." 



