262 Annals of the Carnegie Museum. 



hh. Adipose fin short; gill-rakers short, lanceolate; dorsal rays 21-31; 

 anal in male bilobed (in all species ?), in the female falcate. 

 j. Individual dorsal rays of the male prolonged, filiform; teeth 

 of the front series incisor-like and close to the posterior 



series Myleiis Muller & Troschel. 8. 



jj. Individual dorsal rays not prolonged; teeth various. 



Myloplus Gill. 9. 



The number of species available for study do not warrant a synopsis 

 of the various genera. 



I give below a list of the specimens in the Carnegie Museum, with 

 descriptions of some new species and notes on some of the old species. 



VII. Genus Catoprion Muller & Troschel. 

 27. Catroprion mento (Cuvier). 



5724 C. I\I. 117 mm. Sautarem, Dec. 15, 1909. Haseman. 



5725 C. M. 105 mm. Rio Boaventura, June 16, 1909. Haseman. 



5726 a-c. C. M. 47, 57, and 107 mm. Maciel, Rio Guapore, Aug. 

 10, 1909. Haseman. 



5727 C. M. 87 mm. Bastos, June 28, 1909. Haseman. 



5728 C. M. 67 mm. Rio Jauru, June 2, 1909. Haseman. 

 Head 3.5; depth 1.66-2; D. 15-18; A. 36-38. 



Vm. Genus Colosoma Eigenmann. 

 28. Colosoma mitrei (Berg). (Plate LII.) 

 6536 a. C. M. One, 315 mm. Caceres, INIay 27, 1909. Haseman. 

 Head 3.8 ; depth 2 ; D. 17; A. 23 ; serrae 60 -f 7 ; scales about 55-140- 



54- 



29. Colosoma bidens (Agassiz). 



5633 a. C. I\I. One, 165 mm. to end of middle caudal rays. Manaos, 

 November 16, 1909. Haseman. 



5634 a-d. C. M. Four, 160-220 mm. Santarem, Dec. 16, 1909. 

 Haseman. 



6535 a. C. M. One, 445 mm. San Antonio de Rio Madeira, Nov. 2, 

 1909. Haseman. 



IX. Genus Piaractus Eigenmann. 

 30. Piaractus nigripinnis (Cope). (Plate LIII.) 



Myletes nigripinnis Cope, Proc. Am. Philos. Soc, 1S7S, p. 693 (Peruvian Amazon);. 

 Steindachner, Flussf. Sudam., Vol. II, 1881. p. 25, pi. vii. fig. I (Teffe); 

 Eigenmann & Eigenmann, Proc. U. S. Nat. Mus., Vol. XIV, 1891, p. 61; 

 Ulrey, Ann. N. Y. Acad. Sci., \'ol. VII, 1895, p. 300 (Brazil). 



