68 CONNECTICUT GEOL. AND NAT. HIST. SURVEY. [Bull. 



D. 8; C. 15; A. 8. 



A regularly fusiform species attaining a total length to the 

 base of the caudal fin of about 20 cm., the maximum depth oc- 

 curring shortly behind the pectoral fins and amounting sometimes 

 to nearly one-half the total length. The dorsal and ventral con- 

 tours are more strongly arched than in 5'. fultus, but the relative 

 position and size of the fins are about the same for both species. 

 Dorsal, anal, and pectoral fin-fulcra relatively shorter than in 

 5". fultus. Apparently three dorsal fin-fulcra originate on the 

 dorsal line over the interneurals. The fifth dorsal fulcrum has its 

 origin on the anterior margin of the anterior ray at a considerable 

 distance from its base, and is about one-third as long as the 

 anterior fin-margin. Pectorals with upwards of twenty fulcra. 

 Ridge-scales moderate, spiniform, the one immediately in advance 

 of the dorsal fin slightly produced into a point behind. Scales 

 frequently serrated, those below the lateral line on the flanks 

 tending to become bi- or tridentate on the postero-inferior angle. 



This is a deeper-bodied species than any thus far considered, 

 its rather strongly convex outline marking a transition between 

 the types presented by S. fultus, for instance, and 6". ovatus. 

 Indeed, the approach to the last-named species in this respect is 

 sometimes so close as to make a rigid distinction difiicult without 

 the aid of other characters. In the case of the specimen selected 

 for illustration in Plate IV, Newberry himself appears to have 

 been in doubt whether to refer it to 5". micropterus or S. ovatus, 

 but finally decided in favor of the former, as shown by MS. 

 records accompanying the original. The most reliable means 

 for identifying the present species is furnished by fin characters, 

 the details of which have been carefully worked out by Dr. Eaton 

 in his paper of 1903, and are incorporated in the above definition. 



Remains of this species are fairly abundant in the Connecticut 

 Valley Trias, and show considerable variation of size; that is 

 to say, young individuals occur somewhat numerously, so that 

 gradations may be traced up to the maximum recorded by New- 

 berry. He states that the largest individuals known to him attain 

 a length of ten and one-half inches, and the smallest are " only 

 about three and one-half inches long." Corresponding with 

 the last given dimension, and otherwise agreeing with the char- 

 acters of this species, is the holotype of the late Mr. S. Ward 



