SOME FISHES OF THE FAMILY LEIOGN ATHIVM. 
99 
SOME FISHES OF THE FAMILY 
LEIOGNATHID/E. 
By Gilbert P. Whitley, Ichthyologist, The Australian Museum, Sydney. 
(By permission of the Trustees of The Australian Museum). 
(Plates XIII-XIV and one Text-figure). 
In the present paper, several hitherto little-known species of Pony Fishes 
(Leiognathidse) are redescribed and figured from their types or from authentic 
specimens, and an attempt has been made to classify them into recognizable genera. 
This has been possible mainly through the kind help of Mr. H. A. Longman, who 
forwarded me practically the entire collection of Leiognathidse in the Queensland 
Museum for study and comparison with the Australian Museum and Endeavour ” 
collections in Sydney. I am also under obligation to Miss Joyce K. Allan, of the 
Australian Museum, for most of the illustrations, which render the species easily 
determinable. 
The family Leiognathidse, as understood here, is substantially the same as that 
indicated in Jordan’s ‘‘ Classification of Fishes,” and may be defined as follow's : — 
Five to six branchiostegal rays ; jiseudobranchiee present ; eyes large, on the 
sides of the head ; mouth remarkably protractile ; suborbitals not or but feebly 
ossified, no subocidar shelf ; lower edge of preoperculum generally serrated ; gill- 
membranes narrowly joined to isthmus ; body compressed, generally elevated ; air- 
bladder terminating anteriorly in two liorns, pyloric appendages few^ ; scales small, 
cycloid ; dorsal continuous, with eight spines (normally) and from fifteen to seventeen 
rays ; anal with three sj)ines and thirteen or fourteen rays ; a procumbent spine 
before dorsal and anal fins and a row^ of not very prominent bucklers along bases of 
soft dorsal and anal fins ; colouration generally silvery, darker above, with or without 
dusky or black markings. 
KEY TO TEfE GENERA. 
A. Mouth protractile horizontally ; mandible vertical . . . . . . . . . . Secutor, 
AA. Mouth protractile downwards ; mandible oblique. 
B. Second dorsal spine more than twice as long as third. (Second ana Ispine also produced. 
Supi'aorbital smooth ; teeth villiforrn ; body very deep ; breast 
naked) . . . . . , . . . . . . . . Aurigequula, 
BB. Second dorsal spine not so produced. 
C. Seven dorsal spines and more than 18 rays . . . . . . . . . . Argylepes. 
CC. Eight (abnormally 9) dorsal spines; less than 18 rays. 
D. Body elongate, its depth 3 or more in standard length . . Macilentichthys, new genus. 
DD. Body deep, doj')th generally about 2-2J in length. 
E. vStrong liooked teeth in jaws . . . , , , . . , . . . Gazza. 
EE]. Teeth weak, small. 
