8 MEMOIRS OF THE QUEENSLAND MUSEUM. 



in the autumn. Neither of these fishes showed the slightest traces of spawning 

 though, if they breed in the river, it is incredible that the season selected for the 

 deposition of its ova by a fish notoriously fond of warm sheltered spots, should 

 be other than one of the two seasons during which my informant forwarded them. 

 Mr. Rose, however, is of opinion that these fishes do not breed, at least not in the 

 river, and he bases his opinion on the facts, certified to me by him, and through 

 him to me by other residents of the district, that the examples caught vary but 

 little in size, the usual length being from fourteen to eighteen inches, that no 

 young fish have ever been observed, that no matter at what season of the year 

 they are captured no milt or roe has ever been found in the ovaries, that thej'^ are 

 always in fine condition, and finally that they infinitely excel the estuary Perch 



in flavor. 



' ' The obvious inference is that certain individuals having made their way 

 into the Snowy River at its entrance into the ocean gradually work upwards and 

 eventually find themselves in the pool below the Falls, and being unable to 

 proceed, remain there until captured or swept downward by flood to the estuary 

 again; these latter having, since their enforced return into calmer and warmer 

 waters, grown sybaritic and fat, may possibly be Castelnau's 'not very common' 

 L. aniarcticus, which he describes as 'silvery' and 'very savory.' " 



The sterility of those fishes, which remain permanently in the pools below 

 the Falls, would be satisfactorily accounted for by the coldness of the water. 



Having now cleared the way I shall proceed to discuss the status of the 

 latest claimant to specific honors, Mr. Stead's Percolates fluviatilis. 



Stead (4) insists on 



(a). ^'The far more elongate habit." 



(3) In the four New South Wales examples on which these remarks are 

 wholly based the extreme variation in the depth of the body to its length is 244 

 to 2-87. This is by no means excessive and shows incontestably on how slender a 

 foundation this character rests. In any case the somewhat more slender habit of 

 the fluviatile form and its rather longer and stronger caudal peduncle may 

 clearly be accounted for by the fish's permanent occupation of swiftly running 

 water, as compared with the more equable ebb and flow of the estuarine tideways 

 which P. colonorum mostly affects. 



(&). "The Twn-excavate character of the upper profile of the head, which in 



P. colonorum is universally concave — often highly so." 



This contention has been dealt with above {see p. 2). It is interesting, 



nevertheless, to point out that in Boulenger's description of the species, he, with 



six specimens before him drawn almost assuredly from estuarine sources, writes 



"upper profile of head sometimes concave." The italics are mine. 



(c). "The relatively greater thickness as compared with the body-length." 



This is a character of minor importance. The forces contributory to the 

 formation of a more slender type of fish (see "a") are also doubtless at work 



