the Ichthyology of Australia. 



123 



second spine is just perceptible higher up, near the superior angle of 

 the gill-opening : this point is conspicuous enough in the skeleton, 

 the bone being cut away in a semicircular arc between it and the 

 principal point. There is no peculiarity in the scales which conceal 

 the supra- scapular and humeral bones. 



The teeth, which are, singly, but just visible to the naked eye, are 

 disposed in villiform bands, very densely crowded ; and by the aid 

 of a microscope are seen to be very short and obtuse, a few scattered 

 ones near the symphysis being more so than the rest. The dental 

 surface on the intermaxillary is concave and inclines much inwards, 

 receiving that of the lower jaw, which is convex. On both jaws it 

 tapers as it recedes from the mesial line. The chevron of the vo- 

 mer, resembling an inverted A, is armed, together with the edge of 

 the palate bones, with very minute villiform teeth. 



— B.7- 



7; D.12|12; 



A.3|5; 



C.12f; 



V.l|5; P. 



13 ; 1st specim 



7- 



7; 13|9; 



315; 



12f; 



1|5; 



13; 2nd — 



7- 



7; 13|10; 



3|5; 



12f; 



1|5; 



14; 3rd — 



7- 



7; 13|9; 



3|5; 



12f; 



1|5; 



13; 4th — 



7- 



7; 13|11; 



3|5; 



13; 



115; 



13; C. & V. 



The narrow branchiostegous membrane is supported by seven cy- 

 lindrical rays, the two lower ones being short, very slender, and 

 easily overlooked. The gill-opening is wide. The dorsal varies in 

 different individuals more than is common among the acanthoptery- 

 gian fishes in the number of its soft rays, viz. from nine to twelve, 

 the last one being in each case deeply divided. One specimen also 

 has a spine fewer than the rest. The fin commences a little behind 

 the edge of the preoperculum ; the spinous portion is arched and oc- 

 cupies twice the space of the soft rays, which rise above the poste- 

 rior spines, and are like them oblique. The anterior spines are the 

 strongest ; the first is half the height of the second, and when the fin 

 is fully extended inclines forwards ; the third is the tallest, but is 

 very little higher than the second and third ; the membrane is more 

 deeply notched between the first three spines than in the succeeding 

 part of the fin ; the remaining spines decrease very gradually in suc- 

 cession, the thirteenth being a little taller than the first, and about 

 one half the height of the soft part of the fin, which has a rounded out- 

 line. All the spines after the second one are slightly curved. There 

 are no scales on the fin before the third spine, but more posteriorly 

 a little triangular fillet of scales inclines against the fore side of each 

 spine, the fillets increasing successively in size, and the base of the 

 soft fin is densely scaly. 



The anal commences far behind the anus and nearly opposite to 

 the middle of the soft dorsal. The first spine is short, tapering and 

 acute, and convex before and behind, whereby it is prevented from 

 reclining against the second spine, which is very long, strong, 

 slightly curved and compressed in an opposite direction, having its 

 anterior and posterior edges acute. The membrane slopes off from 

 it to the point of the third spine, which is one-fourth part shorter, 

 producing an acute notch in the fore part of the fin. The third 



