SOUTH AMERICAN NEMATOGNATHI. 387 



Twelve specimens, length .11-. 23 m. Rio Parahyba; 

 Itabapuana; Muriahe. 



LXXV. OXYROPSIS. 



Oxyropsis Eigenm. & Eigenm. Proc. Cal. Acad. 2d Ser. 

 vol. ii, 39, 1889 (wrightiana). 



Type: Oxyropsis wrightiana Eigenm. & Eigenm. 



This genus differs from Harttia as Hypoptoma differs 

 from Otocindus. The head is depressed, the eyes mar- 

 ginal, the orbit infringing slighty on the lower surface 

 of the head. Tail depressed. A lateral keel. Belly cov- 

 ered with granular plates. Adipose fin none. 



333, Oxyropsis wrightiana, 



Oxyropsis wrightiana Eigenm. & Eigenm. 1. c. (Lake Hyanuary). 

 Type: No. 8055; one specimen .037 m. to base of caudal. Lake Hyanu- 

 ary. L. Agassiz. 



Depressed elongate; the depth about 2 in the width. 

 Head depressed, the snout rounded; occipital margined 

 by two nuchal plates; interorbital convex; nares above the 

 anterior margin of the orbit; surface of the head and all 

 the scutes with longitudinal series of small spines; no 

 keels on the head. Lower surface of the head as in Hy- 

 poptoma. Eye 2J in the snout, 5J in head, 2| in the in- 

 terorbital. Teeth well developed; lower lip convex, pap- 

 illose. 



Anal groove bounded laterally and posteriorly by a 

 horse-shoe shaped plate, anteriorly by the large shield- 

 shaped anal plate. Belly with three series of plates 

 which are separated anteriorly; thorax with two pairs of 

 large plates. Four series of plates covering the body, 

 the lateral series with a median keel which is strongest 

 above the tip of the anal. 



Distance of dorsal fin from tip of snout about 2| in the 

 length, the first dorsal ray equals the distance between 

 base of pectoral and tip of snout. Caudal fin damaged. 



