280 Sir J. Richardson on Australian Fish. 



Cheilodactylus aspersits, Richardson. 



Cheilodactylus carponemus, Richardson, Zcol. Trans, vol. iii. p. 99, 

 exelus. synon. 



Radii.— Br. 6; D. 17|27; A.3|ll; C. 13f ; P. SetVII.; A. 1,5, 

 specimens. 



This fish frequents Port Arthur in "Van Diemen's Land, and Dr. 

 Lhotzky says that it is never taken at Sydney. In the ' Zoological 

 Transactions' for 1841 (vol. iii. p. 99) there is a notice of it, to which 

 the reader is referred ; but it is necessary to state that the number 

 of fin rays there given are those of Ch. carponemus, as expressed in 

 the ' Histoire des Poissons.' I there pointed out some of the discre- 

 pancies between the examples of this fish I had then before me and 

 the description and figure of carponemus in the work just referred 

 to ; but being at that time very imperfectly aware of the number and 

 variety of the Cheilodactyli existing in the Australian seas, I did not 

 venture to indicate it as a proper species. This I am now enabled to 

 do, after a careful comparison of the specimens then commented upon 

 with Mr. Neill's example of carponemus from King George's Sound, 

 the exact locality of the specimen of the latter described by Cu™r 

 and Valenciennes. 



Ch. aspersus is a higher fish than carponemus, the greatest height 

 of the body being contained only three times and one-third in the 

 total length, caudal included. It is much compressed, with an acute 

 back and a deeply-forked caudal. The more arched form of the 

 spinous part of the dorsal fin, and the much stouter dorsal and anal 

 spines, afford a ready means of distinguishing the dried specimens. 

 The different colours and markings of the recent fish are very appa- 

 rent. The first and last dorsal spines are much shorter than the cor- 

 responding ones of carponemus, and the notch of the fin is conspi- 

 cuous from the greater height of the soft rays. The second anal 

 spine is very stout, and it rather exceeds the third one in length. The 

 preorbitar is smaller than in that species, and its length does not ex- 

 ceed the diameter of the orbit. The face is therefore shorter, and the 

 profile rises more steeply to the dorsal, owing to the greater height 

 of the fish. The elongated pectoral ray, which is the tenth, reaches 

 no farther back than the beginning of the anal. The scales are rather 

 large and much tiled. About fifty-two exist on the lateral line, besides 

 six or seven rows on the base of the caudal, and there are twenty- 

 two rows in the height of the fish. 



Mr. Lempriere, from whom we had the specimens, says that the 

 fish is known at Port Arthur under the name of "the Perch," and 

 has a bright silvery hue with dark spots. The specimens still ex- 

 hibit many dark brown spots scattered thickly on the back and more 

 sparingly on the sides, most of them being rather smaller than the 

 exposed disk of a scale. The vertical fins, particularly the caudal, 

 are more minutely spotted. The top of the gill-cover is blackish, and 

 there is a dark mark on the humeral bone. As is usual in the genus, 

 the inside of the mouth and lining of the gill-opening are purplish- 

 black. Length 12^: inches. Greatest height 3| inches. 



