192 HELLER AND SNODGRASS 



APOGON ATRADORSATUS sp. nov. 



pi. in. 



Type. Cat. No. 6357, Leland Stanford Jr. University Museum. 

 Charles Island. 



Diagnosis. Almost identical with Apogon atricaudus of the 

 Revillagigedo Archipelago, differing from it in having the distal half 

 of the second dorsal black. 



We have examined numerous specimens of Apogon atricaudus in 

 the Stanford University collection and not one of them shows any trace 

 of black on the second dorsal. Our specimens, preserved in the same 

 manner as the others, invariably have the black on this fin. If the 

 Revillagigedo specimens had in life any black on the second dorsal fin 

 it has, in all cases, faded from it, but not from the first dorsal nor from 

 the caudal. In many Galapagos specimens the tail appears to be a 

 little more deeply forked than in the Revillagigedo specimens, but it is 

 not constantly so. 



Description of the Type. Head two and two thirds ; depth three ; 

 eye three; D. VI-I, 9; A. II, 8 ; scales minutely ctenoid, 3-25-11. 

 Maxillary reaching a little back of posterior margin of pupil ; pectorals 

 reaching base of anal ; ventrals reaching posterior margin of anus. 



Snout blunt ; profile of head straight, gently inclined from snout 

 to front of dorsal, slightly concave from this point to front of second 

 dorsal, descending then to base of caudal peduncle, where it forms an 

 abrupt angle with the peduncle ; ventral profile with about same con- 

 vexity as dorsal, but outline from front of anal to base of caudal fin 

 evenly and roundly concave. Second dorsal higher than first; first 

 dorsal spine short (variable in length, in largest specimens about equal 

 to interorbital space, in younger ones shorter) ; second and third 

 spines longest, two and one half in head ; succeeding spines rapidly 

 shorter, so that posterior border of fin is receding ; seventh spine at- 

 tached to second dorsal, as long as second and third ; second and third 

 soft rays of dorsal longest, one half longer than last spine ; posterior 

 rays very short so that dorsal margin of fin posteriorly turns downward 

 and forward; soft anal similar to soft dorsal; tail emarginate (the 

 depth of emargination greater in young specimens). 



Coloration in Alcohol. Brownish, darker above, minutely punctate 

 with black specks ; caudal and first dorsal dusky, second dorsal and 

 anal pale basally, dusky terminally. In life the color was bright red, 

 paler below, with the distal parts of the vertical fins black. 



