South- American CichUd Genus Acara, 343 



Avith 2 series of scales, prseoperculum 'o itli 1 series ; 6 gill- 

 rakers on the lower part of anterior arch. Scales 23-24 ||' 

 Dorsal XIV'^-XV 9-10, commencing above the opercular 

 cleft, the spines only slightly increasing after the fifth, the 

 last nearly ^ the length of head; soft fin extending to middle 

 of caudal or beyond. Anal III 7. Soft dorsal and anal 

 scaly at the ba>e. Pectoral as long as the head ; ventral 

 extending to origin of anal or beyond. Caudal rounded. 

 Caudal peduncle i as long as deep. Olivaceous, with obscure 

 darker cross-bars ; a dark longitudinal band from eye to 

 below the fourth scale of the lateral line ; a dark blotch on 

 and below the sixth to the tenth scales of the lateral line, 

 and another above it extending on to the spinous dorsal ; 

 soft dorsal, anal, and caudal sometimes with dark spots. 



R. Amazon. 



The examples described by Steindachner measure up to 

 110 mm. in total length. 



16. Acara flavilabris. 



Acara yiavilabris, Cope, Proc. Am. Phil. Soc. xi. 1870, p. 572, and 

 xvii. 1878, p. 696 ; Proc. Ac. Philad. 1872, p. 255, pi. xi. lig. 4. 



Closely allied to A. Thayeri, which it resembles in having 

 2 series of scales on the cheek and 1 series on the praeoper- 

 culum, and quite wrongly placed in the synonymy of 

 A. tetramerus by Steindachner and by Pellegrin. Dorsal 

 XVI 9-10. Anal III 7. Scales 24 |. Caudal peduncle 

 apparently more than ^ as long as deep. A dark blotch on 

 the lateral line before the middle of the side of the body ; a 

 dark bar at the base of caudal ; lower lip yellowish. 



River Ambyiacu, Upper Amazon. 



Cope states that all live specimens examined by him agree 

 in having 16 dorsal spines. 



1 7 . Acara frenifera . 



Acara freniferus, Cope, Proc. Ac. Philad. 1872, p. 255; Pellegr. Mdm 

 Soc. Zool. France, xvi. 1903, p. 177 (1904). 



Apparently allied to the preceding species, but with more 

 numerous scales, 28-29 in a longitudinal series. Dorsal 

 XVI 10-11. Anal III 8. Body with dark cross-bars; a 

 blackish spot below the middle of the dorsal fin, connected 

 with the eye by a blackish longitudinal band. 



River Ambyiacu, Upper Amazon. 



