520 PHTSOSTOMI. 



6. ExocoEtus mento, Plato CXXXI, fig. 0. 



Cuv. and Val. xix, p. 124; Bleeker, Snoek. p. 21 ; Giinther, Catal. vi, p. 281. 



Tarexoccetus mento, Bleeker, Exoc. p. 12G, and Atl. Ich. vi, p. 77, Scombres, t. v, f. 6. 



B. xi, D. 10-11, P. 13, V. 6, A. 10-11, C. 17, L. 1. 44, L. tr. 6/2. 



Lengtli of head 4|, of caudal 5, lieiglit of body h\ in the total length. Eyes — diameter 2? to 3 in the 

 length of the head, about 1/2 a diameter from end of snout, and about 1 diameter from the hind edge of the 

 opercle. Lower jaw a little the longer, slightly produced in the form of a tubercle at the symphysis : 

 interorbital space smooth, with two grooves which diverge from the snout towards the occiput, ceasing opposite 

 the middle of the orbit. No barbels. TeeiA— villiform in both jaws, in several rows in the upper, only one in 

 the lower : a large patch of villiform teeth in vomer, and also on the palatines. Fins — dorsal fin elevated as 

 high as the body, and its membrane deeply cleft : 17 to 18 rows of scales between the occiput and origin of this 

 fin, which commences opposite to or slightly before, the first anal ray. Ventrals in some specimens reaching to 

 the anus, in others to the anal fin : the tin arises midway between the anterior edge of the orbit and the base 

 of the caudal fin. Pectoral reaching to opposite the middle or end of the dorsal. Ventral does not quite reach 

 the anal. Lower caudal lobe the longer. Scales — 35 to 38 rows between posterior edge of head and base of 

 caudal fin. Colours — bluish, becoming silvery along the abdomen : dorsal fin black : upper half of pectoral 

 black, having a white edge : ventral white : anal white with a dark mark along its base : upper lobe of caudal 

 white with a black bar along its base : lower lobe grayish. 



Habitat. — Red Sea, East coast of Africa, seas of India to the Malay Archipelago. In the cold season it 

 is occasionally numerous at Madras, but I never obtained it above 4'3 inches in length. 



