59 



THERAPON NIGEK. 



{Murray Black Perch.) 

 D. 12/12. A. f. C. 17. P. 15. L. lat. 89. L. tr. 14/28. 



Height of the body three and one-half times in the total 

 length ; head four and two-thirds in the same ; eye four 

 and one-third in the length of head. Superior profile con- 

 siderably arched, much more so than the lower one ; upper 

 surface of the head naked, the other parts covered with 

 scales ; pra3orbital strongly denticulated ; prasoperculum with 

 its posterior edge rather emarginated, and covered with 

 very strong spines, particularly long on the rounded part, 

 and becoming much smaller on the lower edge, where they are 

 reduced to small denticulations ; operculum terminated by two 

 bunches of flat spines, the first of two and the second of six ; the 

 suprascapula and the caracoid are very strongly denticulated. 

 The lateral line is very irregularly formed, passing sometimes in 

 the centre and sometimes on the edge of the scales ; the num- 

 bers we have mentioned only relate to the numbers of transverse 

 series it crosses ; it does also extend on the base of the caudal. 

 The dorsal is received in a longitudinal sulcate of the back ; its 

 spines are strong ; the three first are shorter than the others ; 

 the membranes of the soft part have each a longitudinal patch 

 of scales placed near the rays, and extending to more than 

 one-third of the height of the fin. The caudal is emarginated ; 

 it is covered at its base with scales of the same nature as those 

 of the body, and others, much more minute, cover the membranes 

 on all their first half. Anal with its spine large and striated ; the 

 spine of the ventrals strong, striated, and longer than the half of 

 the length of the fin. 



The back is grey, but appears dark on account of all the scales 

 having a rather broad, black margin ; the lower part of the body 

 is of a dirty, yellowish white ; the fins are grey ; the posterior 

 part of the caudal black. 



From the Murray River, but scarce. Length of specimen, 

 16i inches. This sort must be nearly allied to the Therapon 

 TInicolor of Grunther {Catalogue) , 



