FISHES PHENOMENAL AND ECONOMICAL. 157 



group just without the pale of the true Gadidte, with which it would otherwise be 

 most naturally associated. With respect to the rudimentary development of the spinous 

 rays, Gadopsis, in addition to its other points of interest, may be regarded as a form 

 that bridges over, in a natural manner, the hiatus that is supposed to subsist between 

 the ordinary spine-finned (Acanthopterygii), and spineless-finned (Anacanthini) fishes. 

 In this direction it would appear to the writer that additional transitional forms, 

 apparently now extinct, probably united this abnormal Anacanthinoid with such 

 Percoids as Oligorus and other allied Australian genera characteristic of the Murray 

 river and its tributaries. Several of these share with Gadopsis a peculiar excavated 

 contour of the frontal region of the head ; the ventral fins, though not jugular, are 

 set far forward, and have two filamentous prolongations, as commonly obtains 

 among the true Gadidae. The peculiar pattern markings of Gadopsis are, it may be 

 further remarked, wonderfully similar to those characteristic of the Murray Cod, 

 Oligorus macquariensis, consisting of a series of darker scribblings and reticulations 

 on a ground colour of olive or golden green, but which are scarcely, if ever, precisely 

 alike in two specimens. This colour pattern, in Gadopsis, becomes speedily obliterated 

 after death, leaving the fish a uniform black hue, from which it takes its characteristic 

 popular title of the " Black-fish." In the case of the Murray Cod, Oligorus, the circum- 

 stance that the foregoing vernacular name should have been relegated to it serves to 

 accentuate the fact that, setting aside the presence of its spinous fins, it presents to 

 the eye of the uninitiated much in common with the external aspect and configuration 

 of the common Cod. This last suggestion is necessarily not adduced as a serious 

 argument respecting the possible affinities of the fish under discussion, but merely as a 

 floating straw indicative of the existence of a probable strong current of positive 

 evidence that may be found flowing underneath. 



It is a peculiarity of the distribution of Gadopsis marmomtus in Tasmania that, 

 in common with the large fresh- water lobster, Astacopsis Franklinii, it is indigenous 

 only to those rivers which flow northwards and discharge themselves into Bass's 

 Straits and does not occur naturally in all of these. This fish has been artificially 

 introduced from the St. Patrick's to the South Esk, one of the northern rivers 

 hitherto deficient in that species, and has since multiplied and thriven therein, showing 

 that there were no special conditions existing that were inimical to its previous 

 establishment in that river. Still more recently, the writer, acting in his capacity of 

 Superintendent and Inspector of Fisheries to the Government of Tasmania, successfully 

 transported to and established the same species in, the Eiver Derwent, whence 



