DISCUSSION OP SPECIES AND THEIB DISTRIBUTION. 



337 



iostegals; qo pseudobranchi®. Small, deciduous scales on body and head; lateral lines 

 indistinguishable. Vertical tins confluent; pectorals entire; ventrals widely separated. 

 each consisting of two filaments. 



This genus is known from a single species taken in tbe Kay of Bengal, off the Madras 

 coast in 1,310 fathoms, — '/'. Hextii, Alcock {Xnn. and Mag. Xat. Hist., 1890, vi, 213., pi. via, 

 fig. 1) from Investigator station 97. 



PTEROIDONUS, Gunther. 



Vtcroidonus, Gunther, Challenger Report, xxn, 1887, 106. 



The lower pectoral rays are incompletely united with the upper part of the fin and are 

 prolonged. Body elongate, compressed, covered with small scales; lateral line incom- 

 plete, close to the dorsal profile. Head oblong, thick, covered with scales. Eye small. 

 Vertical tins united, hut the narrow caudal projecting beyond the short anal and dorsal 

 rays. Ventrals reduced to a simple filament, inserted behind the humeral symphysis, and 

 somewhat distant from each other. Snout broad with rounded profile, including the lower 

 jaw, without barbel. Mouth wide; hands of villiform teeth in the jaws, on the vomer, and 

 palatine hones. Operculum with a straight spine; preoperculum armed. Eight branch- 

 iostegals. Gill-laminae rather short; gill-rakers rather long, lanceolate and widely set ; 

 pseudobranchise none. (Giinther.) 



I'TI'.KOII MINTS QUI.\«(l"AKIUS. 



This genus is represented by a single specimen, of a species called by Gunther, Pteroi- 

 donas quinquarius [hie. cit.), PI. XXII, Fig. B, 14J inches long, obtained by the Challenger 



off the. coast of Japan (station 235), at the depth of 5<>o fathoms. 



DICROLENE, Goode and Bean. 

 In, ml, iic, Goode and Bean, Bull Mns. Comp. Zoiil., x, 202.— GuNTnr.R, Challenger Report, xxn, 1887, 107 



Brotulids with body moderately compressed; head somewhat compressed, with mouth 

 large (in the type species extending nearly to the posterior margin of the eye). The tip of 

 the maxillary much dilated. Eye large, placed close to the dorsal profile. Head with supra- 

 orbital spines; several strong spines on the preoperculum, and one long spine at the upper 

 angle of the operculum. Snout short, not projecting beyond the upper jaw. Jaws nearly 

 equal in front. Teeth in narrow villiform bands in the jaws, on the head of the vomer, and 

 on the palatines. Barbel none. Gill-openings wide; membranes not united. Gills four; 

 gill laminae of moderate length. Gill-rakers rather long, not numerous. Pseudobranchise 

 absent. Caudal not continent, but without a. distinct peduncle. Dorsal and anal tins long. 

 Pectoral rays arranged in two groups, several of the lower ones being separate and 

 much produced. Ventral tins close together on the isthmus, a pair of bifid rays. Brauch- 

 ioMegals eight. Body and head covered with small scales. Lateral line close to the base 

 of the dorsal tin, apparently becoming obsolete on the posterior third of the body. Stomach 

 siphonal. Pyloric <;eca few, rudimentary. Intestine shorter than body. 



Paradtcrolene, Alcock (Ann. and Mag. Xat. Hist., 1889, .">S7), is so close to Dierolene that 

 we are unable to distinguish it. It is represented by a single species, ]>. multifilis (Alcock), 

 he. cit., from the Bay of Bengal, lit:; fathoms, lat. L'(P 17' 30" X., Ion. 88 50' lv, and from 

 the Andaman Sea, east of Port Blair, 271 fathoms, and offthe Coromaudel coast. 

 19S6S— Xo. 2 22 



