GO 



THEEAPON BICHARDSONI. 



(Murray Silver Perch.) 



D. 12/11-12. A. f. C. 17. P. 16. L. 1. about 65. 

 L. lat. 17/25. 



Height of the body three times and eight-tenths in the total length 

 (to the central end of the caudal) ; head four and two-thirds in the 

 same length ; the eye four and one-seventh in the length of the 

 head. The superior profile strongly convex, and rather equally 

 arched ; the inferior almost straight ; general form elongate ; no 

 teeth to the palate ; praeorbital very strongly serrated ; the prseo- 

 perculum rounded, and armed with a series of long spines pos- 

 teriorly, and of shorter ones below. The caracoid is strongly 

 serrated at its posterior margin ; the operculum has two spines, 

 the lowest being the strongest. The upper part of the head is 

 naked, the rest scaly. The dorsal is received in a longitudinal 

 cavity of the back ; its fifth spine is longer than the precedents ; 

 the lateral line extends considerably on the base of the caudal, 

 which is also covered with scales. The caudal is slightly emar- 

 ginate ; the spines of the anal are very strong, particularly the 

 second. 



This species seems very nearly allied to Therapon Ellipticus, 

 Richardson (Datnia); but the number of the scales given by Dr. 

 Grunther seem very different. (L. lat. 85. L. trans. 17/31.) 

 Richardson's figure shows only about 52, which might agree with 

 our sort ; but he mentions nothing about them in his text 

 {Erebus and Terror). 



This fish is very often brought to Melbourne from the Murray. 

 I have also a specimen from the neighborhood of Deniliquin ; 

 but the lower point of its operculum is flat and bifurcated ; this 

 may be accidental. 



The general colour is of a greyish blue. The lower parts of 

 the body are of a dirty white : the sides shaded with yellow ; 

 each scale is bordered with black ; the head has a blueish 

 tinge, with the lips and the lower parts of the head rosy ; eye 

 yellow ; the first dorsal is dark, with the rays purple ; the second 

 has its lower half of a dirty yellow, and its exterior one black ; 



