272 MEMOIRS OF THE CARNEGIE MUSEUM 



129. Tylobronchus maculosus sp. nov. (Plate XXXV, fig. 3.) 



Type, 113 mm. Creek below Potaro Landing. (Carnegie Museum Catalog 

 of Fishes No. 1923.) 



Cotype, one specimen, 28 mm. Wismar. (C. M. Cat. No. 1917.) 



Cotype, twenty-one specimens, 47-68 mm. Rockstone. (C. M. Cat. No. 

 1918a-e; I. U. Cat. No. 12219.) 



Cotype, one specimen, 104 mm. Crab Falls. (C. M. Cat. No. 1919.) 



Cotypes, fifty-one specimens, 65-107 mm. Tumatumari. (C. M. Cat. No. 

 1920o-e; I. U. Cat. No. 12220.) 



Cotypes, nineteen specimens, 97-143 mm. Creek below Potaro Landing. 

 (C. M. Cat. No. 1922a-c; I. U. Cat. No. 12221.) 



Cotypes, three specimens, 97-136 mm. Kangaruma. (C. M. Cat. No. 1921a; 

 I. U. Cat. No. 12222.) 



This species resembles young Erimyzon sucetta. 



Head 3.66-3.75; depth 3.5; D. 12; A. 9 or 10; scales 4-26 or 27-3; eye 1 in 

 shout, 3 in head, 1 in interorbital. 



Heavy, but little compressed, the head very broad; preventral area broad, 

 rounded, with a median series of seven scales to between the anterior margins of 

 the pectoral; predorsal area broad, with a median series of four or five scales and 

 two paired scales near the occiput; occipital process short and broad, reaching 

 about one-sixth to the dorsal; interorbital flat, broad; fontanels tapering to above 

 the nares; a bridge over the posterior margin of the pupil, another over the anterior 

 margin of the eye. 



Cheeks very narrow, covered by the suborbitals; mouth small, the lower jaw 

 with a crescentic margin, included, the mouth inferior; lips thick, maxillary slipping 

 under the preorbital for its entire length, but not concealed by it, reaching to below 

 nares; about nine minute, bifid teeth on each side of the upper jaw; a smaller 

 number of conical or truncate teeth on each side of the lower jaw. Lower pharyn- 

 geals with three series of bluntly conical teeth, the first series, removed from the 

 second, composed of six teeth; the six teeth of the second series much larger, the 

 inner one largest; four or five teeth in the last series; tongue adnate, without 

 free margin; mouth without supplemental ridges or valves. 



Gill-rakers short, dendritic, 10 + 14. 



Scales large, with dentate margin, very regularly imbricate; fins naked; a large 

 axillary scale; lateral line nearly straight. 



Dorsal large, rounded, its origin about equidistant from nares and origin of 

 adipose, its height about 4 in the length; adipose well-developed; caudal deeply 



