no. 1047. FOSSIL CRABS FROM CALIFORNIA— RATHBUN. 343 



Family CANCRID.F. 



CANCER FISSUS, new species. 



Plate XLIX, fig. 1. 



Type.— Cat. No. 165477, U.S.N.M.; U. S. Geological Survey Local- 

 ity No. 4756. 



This crab is found toward the base of the Etchegoin formation 

 near Henry Spring on the east face of l ' 1900 foot hill " 4 miles south 

 of Coalinga, Fresno County, California. 



This horizon is about 800 feet stratigraphically below the bed 

 containing Loxorhynchus grandis Stimpson. 



One specimen showing dorsal view of carapace only. Outer layer 

 of surface absent except along the lateral teeth. Proportion of 

 length to width (measured at the anterior angle of the eighth or 

 penultimate side tooth) as 1 to 1.45. Convexity and areolation 

 much as in C. magister Dana. The depression about the cardiac 

 region is deeper than in C. magister and the region itself is more 

 distinctly divided in the middle into two elevations. 



The anterior angle of each lateral tooth scarcely projects sideways 

 beyond the tooth immediately in front of it. The teeth are sub- 

 truncate, separated from one another by shallow V-shaped notches 

 and long closed fissures; they are eight in number (including the 

 tooth at the outer angle of the orbit), and are irregular in size and 

 shape; the first, third, fifth, and seventh are larger than the inter- 

 vening teeth; the shape of the ninth tooth (at the lateral angle of 

 the carapace) is not clear, but it is very narrow as is customary in 

 the genus; the fifth, sixth, seventh, and eighth teeth each have a 

 small horny point at their anterior angle. The surface of the teeth 

 is granular. The most anterior tooth visible on the right side is very 

 evidently the outer tooth of the orbit, the close granulation charac- 

 teristic of the margin being continued along the inner side of the 

 tooth, which forms a part of the upper border of the orbit. The 

 margin of the first five teeth is preserved on the right side, while 

 that of the third to the eighth inclusive, as w r ell as part of the margin 

 of the second and ninth teeth, is visible on the left side. 



Very little of the front is preserved ; that is, the tip of a blunt 

 median tooth, the tip of a much smaller lateral tooth on the right not 

 far from the middle, and beyond this last a cavity which may repre- 

 sent still another tooth before the frontal border curves into the tooth 

 which forms the inner border of the orbit. The latter is visible on 

 the left side of the specimen, as are also the two fissures of the orbital 

 margin. The fissures are closed on the margin of the orbit, but widen 



a Proc. Acad. Nat. Sci. Phila., VI, 1852, p. 73; Crust. I'. S. Expl. Expert., I, 

 1852, p. 151 : atlas. 1855, pi. vn. fig. la-d. 



