^'^ISDo'."] PROCEEDINGS OF THE NATIONAL MUSEUM. 323 



ACANTHURID.E. 



78. Acanthurus coeruleus (Blocb). 



One large specimen. Deep blue, with wavy, pale blue horizontal 

 lines on side of body; fins blue; anal with dark longitudinal streaks; 

 pectoral yellow ; edge of caudal black. Caudal lunate. 



79. Acanthurus hepatus (Linuteus). 



One adult. Very dark; sides with narrow black cross-bars; fins 

 almost black. Caudal slightly lunate, the lobes subequal. 



80. Acanthurus bahianus Ciistehiau. (Jc<inilinriis tractus Poey). 



Three specimens. Identical with Cuban examples and evidently be 

 longing to the species tolerably figured by Castelnau as Acaiithuyns 

 bahianus. 



This species is easily distinguished from A. hepatus by the forked or 

 deeply lunate caudal, the upi)er lobe of which is much the longer and 

 falcate, often filamentous at tip. In this species both dorsals are marked 

 with about eight dark lines parallel with the margin of the fin. The 

 general color is brown, paler than in A. hepatus, and blotched with 

 paler below. 



POMACENTRID.E. 



81. Poniacentrus fuscus Ciiv. and Val. ( romacetitna rariahilis Casteluan.) 



The numerous specimens of this species from Bahia and the Abrolhos 

 differ much among themselves in coloration, these differences appar- 

 ently corresponding to different stages in growth. 



The larger sj)ecimens, corresponding to the types o^ fuscus, are nearly 

 black, with a few blue i)oints on the head and a black axillary spot; 

 the fins all black ; no spot at base of last ray of anal. 



Other smaller specimens are dark yellowish olive, the fins black, a 

 black axillary spot ; base of dorsal dark, but without spot ; blue points 

 on head ; no dot on last ray of anal. 



A stdl smaller one, 2\ inches long, is black, with the fins dark ; blue 

 points on head ; a black spot on base of jiectoral ; a large black spot on 

 soft dorsal, surrounded by blue points. A similar but smaller ocellus, 

 bordered with blue on the back of tail. A white spot at base of last 

 ray of anal. 



All these specimens I refer to Fomacentrns fuscus, and these varia- 

 tions in color correspond to those iu the very similar Pacific coast spe- 

 cies, Pomacentrus rectifra'nnm. The S[)ecics called hairdi, analigtitta, 

 and favilatus seem to be, as Giinther has indicated, stages in the growth 

 cf P. reciifrwnum. 



A study of this species has led me to reco'npare the specimens col- 

 lected by me at Pensacola and identified as leucostictus and obscuratus. 



