42 FOSSIL FISHES OF LOMPOC 



which distinguishes the new genus ATKINSONELLA, of uncertain relation- 

 ship. It is named for William Sackston Atkinson, natural history artist 

 of Stanford University, in recognition of his interest in restorations of 

 these ancient fossils. The type of the species (No. 511) is 9y 2 inches 

 long (in life about 13). The head is crushed, and the anal and caudal 

 fins destroyed : otherwise the specimen is in good condition. 



Head about 4 in length to base of caudal ; depth about 4%. Ver- 

 tebrae longer longer than deep, rather smooth, each mesially constricted 

 and with two ridges and three grooves ; the number probably 24 ( 16 

 preserved). Neural spines moderate, directed upward and backward, 

 the anterior more curved and directed more backward; ribs strong. 



Dorsal fin nearly continuous, the rays about IX, 17, not certainly 

 counted ; first part of 8 to 10 slender spines, the third longest somewhat 

 more than depth of body ; the others progressively shorter ; soft rays 

 long, and apparently all short ; pectoral fin rather short, acute ; the upper 

 rays longest, about 3 times in depth of body. Ventrals inserted just be- 

 hind them; the fin, if correctly interpreted, a little longer than the pec- 

 torals and of about 8 slender rays. Unfortunately this very exceptional 

 character is uncertain as the fin as preserved may be a misplaced fin, 

 possibly a pectoral from the other side. 



Scales small, of unique form, largest on the thorax, and rather loosely 

 attached, being scattered in the matrix about the fish. Each scale is 

 rounded in form, with entire edges, but marked by 6 to 9 sharp ridges 

 which diverge forward and upward, about 100 in a lengthwise series. 



