181 



dorsal rays elevated, 1 more than those of anal. Pectoral as long 

 as the head excluding the snout. Ventrals placed close together 

 like two spines, the rays being minute. Anterior anal rays as long 

 as the head. Caudal emarginate. Lateral line makes a long, low 

 curve, becoming straight nearly below last fourth of dorsal. Colour 

 silvery, with purplish reflexions, especially about the anal fin: 



Fig. 62. Psettus argenteus. 



the back is yellowish green, which after death rapidly assumes a 

 leaden hue. One rather wide black band passes directly downwards 

 from the nape through the centre of the eye ; a second from oppo- 

 site the first three dorsal spines goes as far as the opercle. Part 

 of the dorsal is stained with black, as is also the anterior portion 

 of the anal though to a less extent. Pectoral and ventral colour- 

 less ; caudal yellow, with a narrow black posterior edge. 



Hcib. Bed Sea, east coast of Africa, seas of India, Malay Archi- 

 pelago, Australia, and Polynesia: attaining at least 7 inches in 

 length. Most common in Malabar during the monsoon months. 



9. Genus PLATAX, Cuv. & Yal. 



Branchiostegals six; pseudobranchiee. Body compressed and 

 mnch elevated. Eyes lateral. Cleft of mouth small ; snout short. 

 Teeth setiform, trilbbed at their summits, some present on the vomer. 

 A single dorsal fin with from three to seven spines, which are 

 nearly hidden; anal with three continuous with the rest of the 

 fin ; ventrals well developed. Scales ctenoid, of moderate or small 

 size, extended on to the vertical fins. Lateral line unarmed. 

 Air-bladder simple. Pyloi-ic appendages few. 



Geographical Distribution. Indian Ocean. 



