266 ACAXTHOPTERTGII. 



FA3IILY, XXII—PSEUDOCHROMIDES, Mull and Troscli. 



Branchiostegals from five to seven: pseudobranchisB. Body more or less elongated. Eyes more or 

 less lateral. Cleft of mouth oblique. Bones on the head unarmed or obtuse points on the opercle : head 

 not cuirassed. The suborbital ring of bones articulates vsrith the preopercle. Teeth in the jaws, present 

 or absent on the vomer or palatines. Dorsal fin consisting of two portions which are connected, 

 usually more rays than spines : anal similar to, or of less extent than the soft dorsal : ventrals thoracic 

 or jugular : pectorals without appendages. Body scaled. Scales feebly cycloid or ctenoid. Lateral-line 

 interrupted or incomplete. Air-vessel present or absent. Pyloric appendages, when present, in small 

 numbers. 



Bleeker, -witli muck reason, objects to the union of the Genus Opisthogmtlms -with the Pseudo- 

 chromides. He considers the Opisthognathids as forming a distinct family, intermediate between the 

 Blensiids and Pskudocheomides, and distingnished by having a scaleless head, cycloid scales, edentulous 

 palate. Ventral fins well developed and jugular, possessing five soft rays, the two anterior of which are simple, 

 thick, and elongated : dorsal and anal spines very weak and flexible, whilst the number of rays in the anal about 

 equals those of the soft dorsal : caudal with twelve branched rays. 



SYNOPSIS OF GENERA. 



1. Ojnstliognatlms. Cleft of mouth large. Palate edentulous. Scales cycloid. Lateral-line incomplete. 

 Red Sea, those of India to the Malay Archipelago, also Brazils. 



2. Fseiidochnmis. Lower jaw the longer. Teeth in jaws, yomer, and palate. Scales ctenoid. Lateral- 

 line interrupted. 



Genus, 1 — Opisthognathus, Cuv. 



Gnatltypops, Gill. 



SrancMostegals six : pseudobrancliiai. Body more or less elongated, and posteriorly rather compressed. Upper 

 profile of snout parabolic. Eyes lateral, large. Cleft of mouth deep, the upper jaw being either prodiieed in a styli- 

 form process to heyond the angle of the jn-eopercle, or truncated a little behind the level of the hind edge of the eye. 

 Fine teeth in jaics, with an otder erdarged roio : palate edentidous. Dorsal and anal spines weak and flexible 

 (10-13), rays (13-17) similar to those of the anal: anal icith two flexible spines: ventrals jugidar : pectoral rays 

 branched. Scales cycloid, small. Lateral-line not continued so far as the caudal fin. Air-vessel small. Caxal 

 appendages absent. 



Geographical distribution.— Bed Sea, those of India to the Malay Archipelago and beyond, also Brazil. 



This Genus has been subdivided by Mr. Gill into (1) those species in which the maxilla is produced 

 backwards into a styliform process, (2) such as have the maxilla truncated ((^lathypops) . 



SYNOPSIS OP SPECIES. 



1. Opisthognathus nigromarginatus, D. if, A. lC-18. Maxilla produced backwards to beyond angle of 

 preopercle. Bufi" marbled with darker. Dorsarfin light with a black ovate spot between the fourth and eighth 

 dorsal spines. Red Sea to the Malay Archipelago. 



->. Opisthoguathus Bosenbergii, D. \&,, A. iV- IMasilla truncated, reaching to just behind posterior edge of 

 eye. Marbled : dorsal and anal fins black edged, the former with four or five large blotches along its base. 

 Madras to the Malay Archipelago. I'^y 



1. Opisthognathus nigromarginatus, Plate \pif¥i, fig. 5. 



Riippell, Atl. Fische, p. 114, t. xxviii, f. 4; Swaiuson, Pishes, ii, p. 278 ; Giinther, Catal. ii, p. 254: 

 Klunz. Verb. z. b. Ges. Wien, 1871, p. 486. 



Opisthognathus Sonneratii, Cuv. Reg. Anim. ; Cuv. and Val. xi, p. 498; Swainson, Fishes, u, p. 2^8; 

 Jerdon, M. J. L. and Sc. 1851, p. 144. 



Opisthognathus Cuvieri,* Val. Cuv. Reg. Anim. 111. Poiss. pi. 78, f. 3 (? C. and V. xi, p. 498). 



B. vi, D. fj, P. 20, V. 1/5, A. 16-18, C. 12. 



* Some error may have occurred in Cuv. and Val. as the figure, pi. 78, f. .3, does not represent the colours attributed to 

 0. Cuvieri. I ohtainud the 0. Cuvieri at Minlras. but have mislaid it. Amongst Sir W. Elliot's drawings are tliree of this species, 

 1). 25 A. 17. The maxilla is produced bacliwards, as in 0. nigromarginatus. and the membrane has the same black raarlis. Body 

 buff colour, with an irregular che^tuut band along the side, and t« o or three more of whitish spots : head with white spots. Dorsal fin 



