THE AMERICAN TETRAGONOPTERINAE. 273 



WW. Dentary teeth more or less graduated on the 



sides; depth of caudal peduncle more than 



5- head, about 10 to 13 scales in front of the 



dorsal. 



X. Usually 3 teeth in the front row of the pre- 



maxillary; A. 19-24; two maxillary 



teeth; scales 5 to 7-32 to 39-4 or 5. 



55. laeniaius Jenyns. 

 [xx. Three or four teeth in the front row of the 

 premaxillary; A. 21 or 22; one maxillary 

 tooth; scales 6-41-6; second suborbital 

 leaving a naked area but one third nar- 

 rower than the bone. 



see A. gymnogenys, p. 274] . 

 XXX. Usually 4 teeth in the front row of the pre- 

 maxillary; A. 23-28; scales 33-36; one 

 maxillary tooth. 



56. eigmimanniorum (Cope). 

 [xxxx. Two or three teeth in the front row of the 

 premaxillary; A. 23-24; scales 35. Snout 

 more than half the length of the eye. 



see A. giton, p. 271]. 

 vv. Depth 2.6-3.6. 



y. Head 3.75-4.25; snout slightly shorter 



than eye; head heavy; body deepest 



and heaviest over middle of pectorals. 



z. Usually three teeth in the outer row of 



the premaxillary. Anal 17-23. 



57. scabripimiUs (Jenyns). 

 zz. Usually four teeth in the outer row of 

 the premaxillary; a round or oval 

 humeral spot. 

 A. A. 22-24; depth 2.75. Eye equals snout, 1.5 in the interorbital. 



58. scahripinnis laliceps (Cope). 

 AA. A. 17-23; one to seven teeth in the maxillary; depth 2.6-3.66. 



59. scahripinnis paranae Eigenmann. 

 zzz. Four or five teeth in the inner as well as 

 outer series of the premaxillary, very 

 rarely 3 in the outer series. A. 20-25. 

 60. scahripinnis rii'ularis (Ltitken). 

 • yy. Head 3.25-3.6; eye 3.3, snout and inter- 



orbital 3-3.33 in the head, in the adult 

 the snout and interorbital greater than 

 the eye; maxillary in old reaching to 

 below middle of eye. 

 61. scahripinnis longiroslris (Steindachner). 

 yyy. Eye 3 or le.ss than 3 in the head; body 

 deepest at origin of dorsal; A. 21-26; 

 lateral line 37-39; second suborbital 

 covering f of the width of the cheek. 

 62. scahripinnis intermedius Eigenmann. 

 uu. Caudal spot not continued to the tip of the middle 

 rays. 

 B. A. 17 or 18; eye 3-3.5; interorbital 2.5; maxillary with four teeth; D. 9 or 10; scales 6-34 



to 38-5 63. ruhropictus (Berg). 



BB. A. 21-24; eye 2.75-3, equals interorbital; maxillary with three teeth; D. 11; scales 6-33 to 

 35-4.5; lateral line extending to the caudal but sometimes interrupted on the tail; caudal 



spot well defined, not equal to the eye; snout wedge-shaped 64. mutator Eigenmann. 



uuu. No caudal spot; second suborbital narrow, usually 

 leaving nearly half or more than half of the 

 cheek naked. 



