South- American CichUd Genus Astronotus. 347 



scales; caudal rounded. Pectoral asymmetrical, with 15 

 rays ; ventrals a little behind the base of the pectoral. 



A single species from South America. 



The skeleton is very similar to that of Acara tetramerus, 

 but there are 31 vertebrae (16+15), the third and fourth 

 forming a very distinct inferior process for the attachment 

 of the pharyngeal muscles. 



Astronotus ocellatus. 



Lobotes ocellatus, Agass. in Spix, Pise. Bras. p. 129, pi. Ixviii. (1829). 

 Astronotus ocellatus, Swaius. K at. Hist. Fish. ii. p. 229 (1839) ; Eigenm. 



& Brav, Ann. Ac. :N. York, vii. 1894, p. 617 ; Pellegr. M.5m. Soc. Zool. 



France, xvi. 1903, p. 182 (1904). 

 Acara crassispinis, Heck. Aun. Mus. Wien, ii. 1840, p. 356. 

 Cychla rubroocellata, Schomb. Fish. Guiana, ii. p. 153, pi. x. (1843). 

 Hyyroyonus ocellatus, Giinth. Cat. Fish. iv. p. 303 (le62). 

 Acara coinpressus, Cope, Proc. Ac. Philad. 1872, p. 256. 

 Acara ocellata, Steind. Sitzb. Ak. Wieu, Ixxi. 1875, p. 77. 

 Acara hyposticta, Cope, Proc. Am. Phil. Soc. xvii. 1878, p. 697. 

 Astronotus ocellatus, var. zebra, Pellegr. t. c. p. 183. 

 Astronotus /(yjjost ictus, Pellegr. I. c. 



Depth of body 2-2^ in the length, length of head 3. 

 Snout as long as or longer than eye, the diameter of which 

 is 4-4.^ in the length of head, interorbital width 2|— 2^. 

 Depth of praeorbital i the diameter of eye. Mouth oblique ; 

 lower jaw slightly projecting; maxillary very slightly ex- 

 posed, extending* to below anterior ^ of eye; prsemaxillary 

 process extending to above anterior ^ of eye ; cheek with 7-9 

 series of scales, none on the praioperculum ; 7-9 gill-rakers 

 on the lower part of anterior arch. Scales 33-38 j^^, those 

 of the thoracic region considerably smaller than on the sides 

 of the body. Dorsal XII-XIll (XIV) 19-21, commencing 

 above the opercular cleft, the spines slightly increasing in 

 length to the last, which is ^ the length of head. Anal 

 III 15-16. Pectoral nearly as long as the head. Caudal 

 rounded. Caudal peduncle 5-^ as long as deep. Brownish, 

 with a blackish ocellated spot on the upper ^ of the base of 

 caudal and sometimes 2 or 3 more on the base of the soft 

 dorsal ; pectoral with a blackish spot on the inner side near 

 the base. 



Guiana ; R. Amazon ; R. Paraguay. 



1. (255 mm.) TcS6. Mr. Salmiu. 



2. (Skeleton.) Teffe. Prof. A. Agassiz. 



3. (240 ram.) Para. Dr. E. A. Uoldi. 



4. (250 mm.) Carandasinho, Matte Grosso. Dr. A. Borelli. 



5. (225 mm.) Manaos. Paris Museum. 



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