1550 Bulletin 4.7, United States National Museum. 



of spinous dorsal, usually not deeply incised nor lobed, the soft part more 

 or less elevated, its last rays gradually shortened; lower limb of preopercle 

 usually more or less scaly; preorbital narrow without deep notch; anal 

 fin similar to soft dorsal, with 2 spines, of which the second is much the 

 larger ; soft rays 12 to 16 ; dorsal spines with a sheath of large scales, the 

 membranes of both dorsal and anal covered high up with small scales; 

 caudal fin more or less forked, the lobes rounded; lower pharyngeals 

 triangular; branchiostegals 5 or 6. Species numerous, in the tropical 

 seas. Species chiefly American, extremely variable in form and color, the 

 brilliant coloration apparently dependent on surroundings. The species 

 are little known and the classification of those found in the West Indies 

 is, in default of material, largely guesswork. 



Eupomacentrus, as understood by us, differs from Pomacentrus chiefly in 

 having but 1 series of teeth in each jaw. In Pomacentrus an inner series 

 of a few teeth is present. Parapomacentrm and Amblypomacentrus differ 

 from Eupomacentrus chiefly in the different scaling of the head. This is a 

 minor character, and perhaps all 3 should be united under the oldest name, 

 Parapomacentrits. 



The following analysis of species has very little value. Perhaps all our 

 Atlantic species (omitting planifrons} are reducible to 2, fuscus and lenco- 

 stictus, and these 2, if really distinct, can not always be separated with cer- 

 tainty; leucorus and flavilatus are certainly distinct from fuscus, and thus 

 far we have found rectifraanum also distinguishable. Our species, so far as 

 known, all belong to the section Eupomacentrus, which is regarded by 

 Bleeker as a genus distinct from Parapomacentrus, being chiefly distin- 

 guished by the naked lower jaw. Perhaps the 2 genera should be united; 

 but not having seen specimens of Parapomacentrus, we hesitate to place 

 our species in it, though they evidently should not be left in Pomacentrus. 

 (svj genuine; Pomacentrus, which is from itobfJLa, opercle; nevrpov, spine.) 



a. Upper anterior profile of head arched. 



b. Depth of body moderate, If to 2 in length, without caudal. 



c. Lower posterior half of body dark, like the anterior half; caudal fin mostly 



dusky. 



d. Pectoral fin with a broad white edge. LEUCORUS, 1960. 



dd. Pectoral fin not edged with white. 



e. Depth of body 1| in length of body (without caudal) ; sides with 

 faint cross streaks. ADUSTDS, 1961. 



ee. Depth of body 2 to 2 in length. 



/. Opercle without distinct dark spot; caudal not tipped with 



orange. 

 g. Anal without distinct blue spot in its posterior axil, 



except in young. 



h. Head with few, if any, small accessory scales. 

 i. Base of pectoral with one black spot. 



FUSCUS, 1962. 

 ii. Base of pectoral with two black spots. 



DIENC^US, 1963. 



hh. Head with very many small accessory scales, 

 especially on forehead and front of opercle. 



RECTIFR^NUM, 1964. 



gg. Anal with a bluish spot at base of last ray; head and 

 fins much spotted with blue. ANALIS, 1965. 



