1 94 1 CATALOGUE OF FISHES OF TORTUGAS z yg 



Its lack of yellow and its less evident blue spotting tend to distinguish P. adustus 

 from P. xanthurus, an earlier name for P. flaviventer. Finally, the difference in 

 ratio of depth to total length which Troschel gave for the two agrees almost pre- 

 cisely with that between a 63-mm. specimen of the species here called adustus 

 and one of P. xanthurus a little larger. At a length little exceeding 70 mm., I 

 think, in the course of normal development the ocellated black spots are merged 

 in the dark ground color. 



Poey's description of P. dorsopunicaus is brief: Its color is blackish. As seen in 

 the water, it has a beautiful blue sheen. The upper and anterior surface of the 

 head and back are red, as is the corresponding part of the dorsal fin. There is an 

 ocellated spot on the dorsal; the caudal fin verges toward yellow. The length is 

 40 mm. 



Beebe and Hollister's Eu pomacentrus rubridorsalis, I think, is the young of 

 P. adustus, described with greater attention to detail. I am unable to fit into any 

 consistent whole the observations of Beebe and Hollister on their new species. 

 They state categorically that it is not a growth stage of any other, but this is not 

 inferred from the presence of ripe germ cells in specimens in hand. Others seen 

 but not captured, they suggest, behaved like adult Pomacentrus and so declared 

 their standing. But there is no reason to believe that the male and female Poma- 

 centrus are more than momentarily paired, no ground for supposing that being 

 paired, the female shares with the male the responsibility for guarding their 

 young. Without very much more precise observation these authors' position can- 

 not be successfully maintained. 



Pomacentrus obscuratus is a name given by Poey in 1875 to no. 586 of his col- 

 lection, which in Reportorio (vol. 2, 1868, p. 327) was listed as Pomacentrus 

 species dubia. The types were sent to the Museum of Comparative Zoology 

 under the manuscript name P. lineatus. They are still in the collection and are 

 representative specimens of P. adustus. 



Depth in standard length in adults about 2.0. Scales with pores in lateral lines, 

 in 40 specimens, 19 or 20; marginal series of scales on preopercular borders nor- 

 mally developed. 



In young fish the markings on the head do not include a pair of lines on the 

 upper side of the snout, but only small round dots of blue, or of white in alcoholic 

 specimens, there and in the interorbital space. Adults are variable in coloration, 

 both shade and pattern being changeable. The black may lighten to dark gray 

 generally or locally. In the latter case a median light stripe may run from the 

 interorbital space to nape and back, or there may appear merely a light spot on 

 the nape, and one on the side under or before the middle of the dorsal fin, with 

 some lightening of the color posteriorly. 



Germ cells are fully matured at least by the first of June. Reproduction con- 

 tinues actively in August, but the actual length of the breeding season is not 

 known. The favorite breeding ground appears to be rocky bottom about the 

 greater coral stacks. Here, usually well hidden from view, the eggs are deposited 

 in patches several inches in diameter. They measure from 0.74 to 0.81 mm. by 

 0.47 mm. Their yolk is yellow. W. H. L. 



