266 ACAXTHOPTERTGn. 



Family, XXII— PSEUDOCHEOMIDES, Mull and Trosck 



BrancMostegals from five to seven : pseudobranchiae. 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 with 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 vrithout 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, with mncli reason, objects to the union of the Genus OpisthognatJms with the Pseudo- 

 chromides. He considers the Opisthognathidj! as forming a distinct famil y, intermediate between the 

 BLEMJIID.S; and Pseudocheomides, 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 ahout, 

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



SYNOPSIS OP GENERA. 



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

 Eed Sea, those of Lidia to the Malay Archipelago, also Brazils. 



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

 line interrupted. 



G«nus, 1 — Opisthognathus, Cuv. 



Gnathypops, GiU. 



Bra/achiostegals six : pseudobrancMce. Body more or less elongated, and posteriorly rather compressed. Upper 

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

 form process to beyond the angle of the preopercle, or trvmcated a little behind the level of the hind edge of the eye. 

 Fine teeth in jaws, with an outer enlarged row : palate ederttulous. Dorsal and anal spines weak and flexible 

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

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

 appendages absent. 



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

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

 backwards into a styUform process, (2) such as have the maxilla truncated (Gnathypops). • 



SYNOPSIS OP SPECIES. 



1. Opisthognathus nigromarginatus, D. \i, A. 16-18. Maxilla produced backwards to beyond angle of 

 preopercle. Bnfi' marbled with darker. Dorsal fin light with a black ovate spot between the fourth and eighth 

 dorsal spines. Red Sea to the Malay Archipelago. 



2. Opisthognathus Bosenbergii, J). i-J, A. ■^. MaxiUa 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. 



1. Opisthognathus nigromarginatus, Plate LVII, fig. 5. 



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

 Klunz. Verb. z. b. Ges. Wien, 1871, p. 486. • » -> r • 



Opisthognathu? Sonneratii, Cuv. Reg. Anim. ; Cuv. and Val. xi, p. 498 ; Swainson, Pishes, ii, p. 278 : 

 Jerdon, M. J. L. and Sc. 1861, p. 144. ^ ' . , , ±' > 



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



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



„ „ . * Swne «rrOT may have occurred in Cuv. and Val. as the figure, pi. 78, f. 3, does not represent the colours attributed to 

 O. f^men. I obtained the 0. Omnen at Madras, but haye mislaid it. Amongst Sir W. Elliot's drawings are three of this species, 

 U. 25, A. 17. the maxilla is produced backwards, as in 0. mgroma/rginaim, and the membrane has th^ same black marks. Body 

 b.uff colour, with an jrregular ehehtnut band along the side, and two or three more of whitish spots : head with white spots. Dorsal fin 



