THYRSOCLES 21 



No. 316 represents a section of the vertebral column, with 22 verte- 

 brae, these short, quadrate, with three strong ridges (grooves) on the 

 side, a characteristic of THYRSOCLES. The long interneurals and many 

 ribs are preserved, but not the head or fins. 



No. 29. Vertebrae quadrate, with deep grooves ; first dorsal mostly 

 lost ; second very perfect, with long, straight interneurals, about 23 rays ; 

 22 long, straight interhaemals ; ribs very short and oblique; interneurals 

 and interhaemals much larger than in TURIO. 



7 A. Thyrsocles escharion Jordan, new species. 

 (No plate) 



About half our specimens of Thyrsocles (280, 15, 20) differ from 

 the type in the relatively shorter interhaemal bones, which become rapidly 

 shortened from the first, the eighth being not more than half the first, 

 which is 21/2 to 2% in depth of the body at the front of anal, this depth 

 being equal to the length of eleven or twelve vertebrae, the body being 

 rather deeper than in T. KRIEGERI. 



In T. KRIEGERI (303, 306, 51) the interhaemals are much longer and 

 nearly equal in length, the eighth being nearly as long as the first and 

 about half depth of body at front of anal, this depth equal to length of 

 nine vertebrae. 



The type specimen (No. 280) of this fine species, 15 inches in length, 

 shows fairly well all parts behind the head. 



Vertebrae 22 -f- 25 = 47, short, subequal, quadrate, little constricted 

 about as deep as long, each with three ridges and grooves along its side. 

 Body fairly robust, depth 4% in body (from gill opening to base of 

 caudal). Caudal peduncle slender, about 2 l /2 in greatest depth. 



Pectoral rays about 16, the fin rather broad, the lower rays shortened ; 

 ventrals mostly obliterated, apparently just behind pectorals ; first dorsal 

 mostly obliterated, the spines slender, close-set, inserted before pectorals, 

 the interneurals weak, about 10 spines traceable at the bases ; interspace 

 between dorsals considerable ; soft dorsal with rather long and strong 

 interneurals, nearly straight, the fin broken; interneurals 16; the fin 

 rays at least as many, probably about 20, the last rays and interneurals 

 obliterated ; anal with long, strong interhaemals, the anterior ones very- 

 oblique, and all parallel, making a conspicuous grate-like appearance. In- 

 sertion of fin rather behind middle of second dorsal ; the fin rather high, 

 apparently falcate, of about 20 rays; caudal widely forked, of about 20 

 rays on each side. The lobes % more than greatest depth of body. In 

 this specimen the axis of each vertebral centrum is turned forward above. 



