2OI 



rally scaly. Upper lip absent, lower lip well developed but not 

 continuous at symphysis. Jaws with villiform bands of teeth, 

 not extending to outside of jaws. Teeth on palatines, on 

 vomer present or absent. Praeoperculum more or less conspi- 

 cuously serrated behind. Anal of about same length as second 





Fig. 65. Polynemus' microstoma Blkr. X 3 /5- 



dorsal, its origin opposite to or behind that of second dorsal. 

 Pectorals with 5 14 free filaments. Scales moderate or small. 

 Gillopenings large, gillmembranes free from isthmus and from 

 each other. 



Distribution: Tropical coasts of Indie, Pacific and Atlantic. 



Key to the indo-australian species of Polynemus 



1. Five free pectoral filaments. 



A. Pectoral rays undivided. 'L.I. 60 65. Distance 

 between origin of ventrals and that of anal much 



less than length of head. Teeth on vomer . . P. plebejus p. 202. 



B. Only 2 or 3 rays of pectorals simple, the other 

 ones divided. 



a. L.l. 47 50. Distance between origin of ven- 

 trals and that of anal much less than length 



of head. No teeth on vomer P. microstoma p. 204. 



b. L.I. 70 75. Distance between origin of ven- 

 trals and that of anal equal to or more than 



length of head. Teeth on vomer P. indicus p. 205. 



2. Six free pectoral filaments. 



A. Pectoral rays 'undivided. Teeth on vomer. 

 a. L.I. 47 50. Pectoral filaments reaching on 

 anal or farther. 

 a. Pectorals longer than head. Longest pec- 



