PSETTODID^ 



Family i. PSETTODID^. 



Eyes on the right or left side ; optic chiasma dimorphic. Dorsal fin not extending 

 forward on the head, the anterior rays spinous. Pelvic fins nearly symmetrical, 

 thoracic, each of a spine and 5 soft-rays. Mouth large, terminal, with straight cleft ; 

 lower jaw prominent ; jaws and dentition equally developed on both sides ; maxillary 

 with a well-developed supplemental bone ; teeth strong ; palatines toothed. Urohyal 

 normal, the lower edge scarcely curved. Pr^operculum with free margin. Nasal 

 organ of blind side scarcely higher than the other ; olfactory laminje numerous, 

 radiating from a rather short central rachis. Vertebra; 24 (10 -f 14) ; praecaudal 

 parapophyses downwardly directed and united to form closed haemal arches. Two 

 post-cleithra on each side ;' pectoral radials well developed. 



A single genus from tropical seas. 



Genus 1. PSETTODES. 



Psettodes, Bennett, 1831. Proc. Comm. Zool. Soc. (12), p. 147 [Pseltodes bekhcri, Bennett]. 

 SphagomorusXope, i860, Trans, .Amer. Phil. .Soc. Philad., xiii,p. 407 [Pleuronectes crumei, Schneider]. 



Body o\ate or rather elongate, not greatly compressed. Eyes separated by a flat, 

 scaled space of moderate width, the upper placed on the dorsal surface of the head. 

 Mouth large, the length of the maxillary more than half that of head. Teeth straight 

 or curved, pointed, some of them with barbed tips ; - in 2 or 3 series in both jaws, 

 those of the inner row larger, depressible, those of the outer row fixed ; a small patch 

 of teeth on the vomer and a single row on each palatine ; patches of teeth on tongue. 

 No gill-rakers, but gill-arches with groups of teeth ; lower pharyngeals very narrow, 

 slender, not united, each with 2 (or 3) rows of slender curved teeth, those of the inner 

 row larger. Most of the soft-rays of the dorsal fin and nearly all those of the anal 

 branched, not scaled ; a low scaled sheath at bases of dorsal and anal ; tip of first inter- 

 haemal spine not projecting in front of anal. Pectoral fins subequal, middle rays 

 branched. Scales rather small, adherent, with fine diverging striae and finely crenu- 

 lated margins. Lateral line well developed on both sides of body, with a low curve 

 above the pectoral fin ; no distinct supratemporal branch ; tubules branched. Vent 

 nearly median, just in front of anal fin ; several pyloric appendages. 



Two species from tropical West Africa and from the Indo-Pacific. 



Synopsis of the Species. 

 T Depth 2j to 2j in length, head 3J to 3§ ; lower jaw 31 to 4J in length of 

 fish (without caudal) ; 32 to 38 scales round caudal peduncle ; caudal 

 fin without dark spots . . . . . . . .1. eritmei. 



II. Depth 2 J to 2 J in length, head 3f to 3I ; lower jaw 4J to 5 in length of fish 

 (without caudal) ; 29 to 30 scales round caudal peduncle ; caudal fin with 

 vertical rows of large dark spots . . . . . .2. belcheri. 



I. PSETTODES ERUMEI (Schneider). 



Pleuronectes crumci. Schneider, 1801, in Bloch, Syst. Ichth., p. 150. 



Hipploglosius erumei, Cuvier, 1829, R. Anim., ed. 3, ii, p. 340 ; Riippell, 1830, Fische Rothen Meeres, 



p. 121; Cantor, 1850, J. Asiat. Soc. Bengal, xviii (2), p. 1198 ; Bleeker, 1852, Verb. Batav. 



Gen., x.\iv, Pleuron., p. 13. 



' According to Chabanaud (1931, Bull. Soc. zool. Fr., Ivi, p. 395) there is only one post- 

 cleithrum on each side. I have examined two skeletons of P. erumei and find two post-cleithra on 

 each side in this species. The bones are closely united, but in each case the suture is quite distinct. 



' See Rendahl, 1921, ' Fauna och Flora,' p. 182, figs. 



