96. POMACENTRIDJ?: POMACENTRUS. 
609 
Family XCVL— POMACENTRID.E. 
[The Fomacentroids.) 
Labroid fishes with the body short, deep, compressed, covered with 
ctenoid scales; lateral line wanting posteriorly; mouth moderate, usu- 
ally with rather strong teeth; vomer and palatines toothless; nostril 
single on each side,* nearly round ; preopercle with its posterior edge 
largely free; dorsal fin single, with the spinous portion longer than the 
soft, which is similar to the soft anal; anal spines 2; ventral fins tho- 
racic, I, 5, the anterior rays longest. Lower pharyngeals fully united; 
branch iostegals 5-7 ; gills 3J; slit behind the last gill very small or ob- 
solete; no labyrinthiform appendage; air-bladder and pseudobranchim 
present; gill-membranes free from the isthmus. Vertebne 12+14. 
Fishes of the tropical seas, simdar in mode of life to the Cluctodontidcc^ 
feeding on small marine animals and plants in the coral reefs. Genera 
10 ; species about 160. 
( Pomacentridw Gunther, iv, 2-64.) 
a. Teeth iiicisor-like, fixed, in one series Pomacentrus, 325. 
aa. Teeth conical, in 2 or more series Chuomis, 326. 
325.— POMACENTRUS Lac^pede. 
Demoiselles. 
(Glyjdiidodon Lac.: Hypsiipops, Pomataprion, awd Euschiatodus Gill.) 
(Lac^pede, Hist. Nat. Poiss. iv, 508, 1802: type CJuetodon pavo Bloch.) 
Body ovate, deep and compressed; the profile steep. Head moderate, 
nearly as deep as long, almost everywhere scaly. Mouth quite small, 
terminal; the jaws equal; both jaws armed with a single series of com- 
pressed teeth, notched or not, immovable. Gill-rakers long; ineop- 
ercle entire, or more or less serrate; preorbital serrate or entire. 
Scales large, strongly ctenoid, the lateral line running parallel with 
the back to near the end of the dorsal fin, at which point it ceases. 
Dorsal fin continuous, with 12 or 13 low stout spines; the soft part 
more or less elevated, its last rays gradually shortened; anal fin sim- 
ilar to soft dorsal, with two spines, of which the second is much the 
larger; dorsal spines with a sheath of large scales, the membranes of 
both dorsal and anal covered high up with small scales; caudal fin 
'As in tlie CichUdw. All other Acanihopteri have two nasal openings on each side. 
Bull. l:7at. Mus. No. 16 39 
