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U. S. P. R. R. EXP. AND SURVEYS ZOOLOGY GENERAL REPORT. 



ray alone is simple, or else not sub-divided. The fulcra extend beyond the two-thirds of the 

 length of all the external rays. 



The number of scales in an oblique series across the body, beginning under the ventrals and 

 extending upwards and forwards, is forty-three : One dorsal median series ; seven from the 

 dorsal region to the lateral line ; and thirteen from the lateral line to the median series on the 

 abdomen. 



In a similar oblique series, taken posteriorly to the ventral fins, there are thirty-seven scales : 

 the dorsal series as usual ; seven from the dorsal region to the lateral line ; and nine from the 

 lateral line to the middle region of the abdomen. The tubes of the lateral line are very con 

 spicuously developed. 



The forms of the scales constituting the middle dorsal series is quite different from all the 

 rest : posteriorly rounded, broader than long, and sub-cordiforrn from the occiput to a certain 

 distance back, becoming sub-elliptical further on and quite lanceolated as they approach the 

 dorsal fin. On the sides of the body they are sub-rhomboid, sub-convex at their upper and pos 

 terior edge, and rather convex at their inferior edge. Towards the caudal region they are sub- 

 trapezoid, angular, posteriorly lanceolated and acute. 



The ground color is olivaceous, spotted with bluish black above and on the sides ; the abdomen 

 being light yellowish or straw color ; the upper surface of the head and snout exhibiting the 

 same spots as the back. The vertical fins are likewise spotted, whilst the pectorals and ventrals 



are of a uniform yellowish tint. 



List of specimens. 



2. LEPIDOSTEUS (CYLINDROSTEUS) LATIROSTRIS, Grd. 



SPEC. CHAR. Body anteriorly cylindrical, deeper than broad (thick), upon its middle; dorsal region sub-convex, broader 

 than the abdominal region. Peduncle of tail very much compressed. Head constituting the fourth of the total length. Eye 

 rather large, circular ; diameter of orbit entering about ten times in the length of the side of the head ; thrice behind its posterior 

 rim. Anal fin somewhat deeper and longer at its base than the dorsal ; the tip of its longest rays extending beyond the insertion 

 of the inferior rays of the caudal fin. Ventrals larger than the pectorals, and inserted nearly midway between the thoracic 

 belt and the origin of the anal fin ; hence nearer the extremity of the rostrum than the convexity of the caudal fin. Bluish 

 grey above ; dull yellow beneath. 



The species here referred to is closely allied to Lepidosteus platostomus, from which it differs 

 chiefly by a broader rostrum, tapering likewise less rapidly forwards. Its width near the apex 

 is half that of its base,, near the angle of the rnouth. The base of the head is a good deal 

 broader than deep. The number of the rays of the fins are as follows : 



D 8 + 1; A 9; C 12; V6; P 10. 



All of them bifurcate and again sub-divide, except the last in the dorsal and anal fins, as well 

 as the innermost in the pectorals, which are simple, else undivided. 



The number of scales in an oblique series across the body, with its initial point under the 

 base of the ventrals, is from forty-six to forty-eight or from forty-five to forty-seven : one dorsal 

 median series ; nine or ten from the dorsal region to the lateral line ; and thirteen from the 

 lateral line to the middle series along the abdomen. 



