Teleosts from Russell Substage. 38 



base of the dorsal fin is subteuded on either side by nn im- 

 bricated series of rather lar^e smooth })ony scutes. The ex- 

 Ijosed parts of these scutes are rhomboids whose two longer 

 sides are directed obliquely forward and downward, as de- 

 termined by the direction of the anterior scute-border, there 

 being one scute on either side for each dorsal ray. The 

 scutes slope outward and downward and their upper borders 

 are in contact with the dorsal rays, while the lower are nearly 

 on a level with the articulations between those rays and the 

 blade-like interneurals. It is probable that these scutes con- 

 stituted a sheath into which, in life, the dorsal fin was de- 

 pressible. Pectoral fin elongate-triangular, reaching nearly 

 half way to beginning of pelvic and to a point nearly under 

 beginning of dorsal, composed of at least 16 rays, of which 

 all are articulated and all, save the first, dissected; pelvic fin 

 abdominal, placed well back of the middle of the torsus and 

 beginning about under posterior limit of dorsal, consisting 

 of one large simple distally articulated ray and 12 or 13 dis- 

 sected soft rays; caudal fin large, strongly and widely forked; 

 pectoral and pelvic fins subtended (apparently on lower 

 side only, of insertion) by scutes similar to the dorsal ones, 

 those of the pectoral arranged in a partly triseriate group. A 

 double series of scutes, representing the fore-base of the anal 

 fin, begins at a distance of about one and one-fifth times the 

 pelvic fin-length back of the insertion of the first pelvic ray; 

 vertebra} upward of 50, their length and depth subequal, 

 gradually becoming relatively small and short in the anterior 

 region; intermuscular bones numerous, especially above 

 vertebral column; scales small, arranged in 50 or more rows, 

 larger anteriorly than posteriorly, (a few especially large 

 ones on nape'?), minutely and closely concentric-striate on 

 the anterior (concealed) part, radiate ly punctate-rugose on 

 the exposed part, which is thickened with cementum, the 

 posterior border toothed; lateral line short (?), very high up 

 on the fiank in the region anterior to the dorsal fin (where 

 alone it has been seen), its distance from the summit there 

 contained about four and a half times in the half girth of 

 the body. 



