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TRANSACTIONS OF THE AMERICAN PHILOSOPHICAL SOCIETY 



Leiognathus. — Boulenger has referred this genus to the Gerridae, but Starks (191 la) 

 after a thorough analysis of its osteology shows that it differs from the Gerridae in many 

 important skeletal characters. Nor is it closely allied with the Carangidae, which it re- 

 sembles externally. This fish has a deep compressed body covered with small silvery scales. 



pntt ; 



TT1X 



Microspathodon chrysurus 



Fig. 128. Microspathodon chrysurus. 



Its supraoccipital is produced into a very high crest which, however, lies wholly behind the 

 frontals, unlike that of the Carangidae. The mouth is small and protrusile with extremely 

 long ascending processes of the premaxillae, which are received into a triangular area on the 

 skull roof. Starks considers (1911a, p. 8) that "the character of its supraoccipital cr^st 

 and its deep pelvic girdle may indicate a connection with the scombroid stem near the place 

 where the chaetodont fishes branched off." Nevertheless Tate Regan in 1913 (a) united 

 the Gerridae with Leiognathus and its allies in the single family Liognathidae, while in 1929 

 (p. 320) he again classes it among those families of marine perches which have "a scaly 

 axillary pelvic process and the maxillary sheathed by the praeorbital," namely the Lutian- 

 idae, Pomadisidae, Sciaenidae, Mullidae, Sparidae, etc. 



Cichlids. — These numerous freshwater fishes of Africa and South America parallel the 



