14 



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



the dorsal and anal fins exhibit a black spot or patch at the base of their posterior margin. 

 Black dots are scattered all over the body, but may not occur in all the specimens. The 

 pectoral fins are of a light olive ; the ventrals, olivaceous upon their base, are greyish towards 

 their extremities. The other fins are greyish olive. 



References to the figures. Plate IV, fig. 1, represents Calliurus diaphanus, size of life. 

 Fig. 2, a scale from the dorsal region. Fig. 3, a scale from the lateral line. Fig. 4, a scale 

 from the abdominal region. 



List of specimens. 



3. CALLIURUS FORMOSUS, Grd. 

 PLATE V, FIGS. 1 4. 



SPEC. CHAR Mouth large, gape oblique upwards. Posterior extremity of maxillary extending to a vertical line passing 

 beyond the middle of the pupil. Eye moderate. Insertion of ventrals situated under the base of pectorals and a little 

 posteriorly to the anterior margin of the dorsal, their tips reaching the vent. Scales moderate. Reddish brown above, 

 spotted with black ; greyish beneath. Soft portion of dorsal and anal fins provided with a black patch. 



STN. Calliurus formosus, GRD. in Proc. Acad. Nat. Sc. Philad. November 1857. 



This species, we venture to say, will prove very closely allied to, if not identical with, 

 C. punctulatus of Rafinesque. But not being able to establish the fact with any degree of 

 certainty, we send it forth under the above appellation. 



The general form of the body is intermediate between that of C. melanops and C. diaphanus. 

 Proportionally as deep anteriorly as C. melanops, it tapers much more rapidly backwards. The 

 cleft of the mouth and the extension of the maxillary bone resemble C. diaphanus most. The 

 eye is smaller than in either of the preceding species. 



The greatest depth of the body, measured upon the thoracic region, is a little more than the 

 third of the entire length, and a little greater also than the length of the head. The nape is 

 quite convex, and the upper surface of the head very declivous. The head itself constitutes a 

 little less than the third of the length. The upper jaw, though longer than the upper, is less 

 protruding than in C. melanops and C. diaphanus. The gape of the mouth is less oblique 

 upwards, and the posterior extremity of the maxillary extends to a vertical line which would 

 pass posteriorly to the middle of the pupil. The tongue is broad, fleshy, and toothless. The 

 eye is of moderate size, sub-circular in shape ; its diameter entering five times in the length of 

 the side of the head. 



The spinous portion of the dorsal fin is lower, or else less arched in its upper outline, than 

 in the two preceding species, whilst the soft portion of the same fin is even more developed than 

 in O. diaphanus ; the posterior extremities of the longest rays being even with those of the 

 anal, and reaching a vertical line which would intersect the insertion of the caudal. The 

 caudal itself is but slightly emarginated posteriorly, and enters about five times and a half in 



