PEOCEEDINGS OF UNITED STATES NATIONAL MUSEUM. 503 



Genus HYBOGNATHUS, Agassiz. 



29. Hybognathus argyritis, Girard. (No. 27,431.) 



Hijhognathus argi/ritis, GiUARD, Pac. K. R. Surv. vol. x, 235 ; Proc. Acad. Nat. 

 Sci. Pliila. 1856, 182. 



Specimens of this species were seined in Horsebunter Creek at Macon, 

 and in the Chickasawha Eiver at EnteriJiise. Some of these have a 

 total length of 4^ inches. 



Genus ALBURNOPS, Girard. 



30. Alburnops taurocephalus, Hay, sp. iiov. (No. 27,439. ) 



This very interesting species resembles much Hyhorliynclms notatus, 

 and therefore recalls strongly Professor Cope's description of Ili/bopsis 

 tuditanus, from Northern Indiana. (See Trans. Amer. Phil. Soc. 18G9, 381.) 

 It is a true Hyhopsis, or Alburnops^ as indicated by the short alimentary 

 canal and the close union of the spinous dorsal ray to the first soft dor- 

 sal. The teeth are 4-4, hooked, compressed, and x^rovided with a masti- 

 catory surfiice. 



The body is stout, somewhat compressed, broad and flat above, with 

 a deep and angulated caudal peduncle. The latter is contained in the 

 body about 3g times. Its depth is one-half its length. The herd is 

 broad and flat above, and at the temiioral region forms an angle with 

 the cheeks. The breadth of the head behind the eyes is equal to the 

 distance from the muzzle to the back of the orbit, and iiearlj^ two-thirds 

 the length of the head. The muzzle is broad and obtuse; but not so 

 truncate as that of Hyborhynclms notatus^ since the i)rofile rounds grad- 

 ually into the snout. 



The mouth is rather small, horizontal, and terminal ; the jaws about 

 equal, the upper heavy. The maxillary hardly reaches a perpendicular 

 from the anterior margin of the orbit. Eye large, 3^ in the head. Head 

 in the length, exclusive of the caudal, 4^ times. Depth about equal to 

 the length of the head. 



Dorsal I, 8 ; A. I, 7. The dorsal begins above the ventrals, is longer 

 than high, and has on the anterior rays, rather below the middle, a 

 black spot. This tin commences nearer the snout than the caudal. The 

 anal is small. 



The scales along the lateral line are rather large and silvery; the 

 formula is 8-43-4. The scales in front of the dorsal fin are small, 

 especially on the nape. 



In color this species is pale yellow, with a dusky tinge given it by 

 numerous black punctulatious on each scale. The sides are silvery, as 

 are also the cheeks and opercles. There is an obsolete dusky band 

 along the lateral line, terminating at the base of the caudal in a small 

 but distinct black spot. The top of the head and snout brown. 



Length of the largest specimen 3 inches, exclusive of caudal. 



