Teleosts from Rlssell Substage. 31 



5; pelvic bones distinct, presenting considerable resemblance 

 to those of Exoco'tus, plate-like, in part roncavo below, bearing 

 an anterior spine-like process; tins large, without rigid spines 

 (unless in case of the dorsal, which is doubtful), subtended 

 by large bony scales or scutes; the dorsal fin with long basis, 

 placed midway of the length of the body, wholly anterior to 

 the pelvic fin; pectoral fin subinferior; pelvic fin abdominal 

 and very posterior; caudal forked; scales ctenoid; lateral line 

 placed high on the sides in the anterior region when present. 



Genus PELECORAPIS. 



Pelecorapis Cope. Report (Hayden) U. S. Geological Survey of the 

 Territories, Vol. II, p. 182. 1875. 



Form compressed and elongate; head naked, orbit large, 

 jaws toothed throughout, the lower jaw projecting beyond 

 the upper; maxillary distinct from premaxillary, forming 

 lateral margin of upper jaw; premaxillary short; pelvic bones 

 consisting of a pair of irregular plates in contact at the 

 median plane chiefly by the long edges of thin wing-like ex- 

 pansions; anterior process of either bone long, tapering, 

 acute, the two of the opposite bones convergent but not 

 meeting; bases of median fins subtended on either side (and 

 in front?) by a single row, those of the paired fins subtended 

 at the lower side by a patch or two- to three-fold row of im- 

 bricated bony scutes; anterior ray of fins (including anal?) 

 simple and, in case of the pectoral and pelvic at least, articu- 

 lated; dorsal fin with moderately long basis, attaining a 

 moderate height in the anterior part and considerably di- 

 minished in the posterior, placed wholly anterior to the 

 pelvic fin; the latter situated far back on the abdomen, re- 

 mote from the large and long, inferiorly placed pectoral; 

 pectoral fin intermediate in length between that of Exocwtus 

 and that of Albula; scales small, in numerous longitudinal 

 rows; lateral line high on anterior region, apparently partial, 

 (sometimes wanting?); vertebne of the posterior to middle 

 trunk region large, those of the anterior region becoming 

 smaller and much shortened. 



