Garman.] 212 [May 2, 



" (Tcenura) Mulleri Castelnau, Anim. Nouv. Amer. Sud. 

 Poiss., p. 102, pi. 48, f. 2. 



Trygon {Tcenura) Henlei Cast., 1. c, p. 102, pi. 48, f. 3. 



Iceniura Mulleri Dumeril, Elasmobranchs, p. 621. 

 " Henlei Dum., 1. c, p. 623. 

 " motoro Dum., 1. c, p. 624. 

 " " Giinth., Cat. vin, p. 484. 



Disk oval, rounded in front, a little longer than wide. Head 

 broader than that of Humboldtii. Eyes, spiracles and nasal valves, 

 as in the preceding. Snout with a small prominence. Mouth larger, 

 with a deep and wide ' indentation on the symphysis in the upper 

 jaws, with five papillae. Teeth much larger than in either of the other 

 species of the genus, unequal, blunt; varying in number of series — 

 from twenty-five to thirty-eight in the upper band — according to 

 age. Adult specimens have two or more rows of large, flattened 

 teeth in the middle of each band. Hinder extremities of pectorals 

 rounded. Ventrals triangular, longer than wide, rounded at the 

 extremities. Tail strong, depressed anteriorly, bearing a sharp 

 dentated spine at a distance from the base equal to half the length 

 of the disk; slender posteriorly, compressed into a sharp keel above, 

 round below, with narrow cutaneous expansions on the top and be- 

 neath. Prepelvic cartilage reaching more than half-way to the 

 shoulder girdle. 



Young naked, brownish yellow on the dorsal surface, with three or 

 more concentrically arranged series of spots of orange encircled with 

 brown. 



Medium sized covered with small harsh scales, a dorsal and two 

 lateral rows of spines on the tail, darker brown with the spots dis- 

 tinct. 



Large ones with the scales on the central portions of the disk 

 larger and scattered; color varying in different specimens from 

 brown with the spots well preserved, to brown with only a blotch of 

 dark brown to mark where the spot has been, or to uniform dark 

 brown. 



Very large specimens have medium sized tubercles near the margin 

 of the disk. 



The claspers are short, subcylindrieal, jointed in the middle of the 

 length. The scales are stellate; each ray is compressed very thin 

 and serrated on the ed^e. 



