4 EDIBLE FISHES OF NEW SOUTH WALES. 



from a single specimen taken in a freshwater pool near Parramatta, the 

 type of which is also missing. We have, therefore, in the restricted genus 

 Percalates no less than five supposititious species, excluding the original 

 P. eolonoritni, all described from a similar and somewhat limited area on 

 what appears to be insufiicient grounds ; that none of the later writers on 

 Australian fishes (Johnston, Catalogue of Tasmanian Pishes, 18S2 ; McCoy, 

 loc. cit. 1878, and Lucas, Census of Victorian Pishes, 1889), except the author 

 (Catalogue of New South AVales Pishes, 1885), venture an opinion on their 

 specific identity or otherwise, is, it must be conceded, a most unsatisfactory 

 state of affairs, and merits, therefore, a more extended inquiry than is usually 

 necessary in such cases. 



In L. shnUis the characters relied on for its separation from the type 

 species are absurdly inadequate ; these are the shorter snout, which is 

 " sensibly less than the diameter of the eye" ; with the majority of fishes the 

 comparative size of the eye to the head and to the snout varies with the age of 

 the individual, the young fish having that organ much larger proportionately 

 than the adult ; as I have shown above the great variation existing between 

 the comparative measurements of the eye and the snout in twenty five 

 specimens of indubitable P. colonorum ranging from Adelaide to the Rich- 

 mond River, it is manifest that the stress laid upon this character is altogether 

 misleading, and must be regarded as valueless ; the coarser denticulations of 

 the preopercle are also a sign of immaturity, and as such unreliable ; in the 

 large series which has passed through our hands specimens have in rare 

 instances occurred in which the teeth of the lower preopercular limb were 

 directed absolutely downwards ; neither this character nor that of the 

 omission of one of the dorsal rays can, therefore, be taken as a valid reason 

 for separating L. similis from Griinther's well known species. 



It is unnecessary to go at any length into the question of the validity of 

 L. anfarcficus, since, with two exceptions, a comparison of Castelnau's descrip- 

 tion with that given above will show that no characters are given, which 

 are not equally common to P. colojiorum. These are the increased number 

 of branchiostegal rays which is stated to be seven in this species as against 

 six which the examination of numerous specimens has shown to be the 

 normal number in P. colonorum as here and elsewhere stated, and also 

 recorded by Professor McCoy. I do not, however, attach any importance 

 to this seeming discrepancy, since it is probable that that number is merely 

 copied from the generic description of Laies given by Gliuther (Catalogue 

 of Pishes, i. p. G7) and which is correct of that genus as restricted to the 

 two species L. niloticus and L. calcarifer ; it may be further pointed out 

 that in few, if any, of his other descriptions of new genera or species does 

 Castelnau take any notice of this important point : the second exception, 

 namely the coloration, is not of sufiicient importance to justify the retention 

 of L. antarticus as a distinct form, and this name also must, therefore, sink 

 into a synonym of the typical species ; further on (p. 5) the author will have 

 occasion to refer to a form which, by a casual observer, would at once be set 

 down as distinct, but which, scientifically examined, is easily seen to be no 

 more than a local variety of the common Australian Perch due to the 

 greatly changed conditions under which it exists ; this form may possibly be 

 the L. antarcticus of Castelnau, though, if so, it is diflicult to say why he 

 should especially designate it the " Sea Perch." 



Of L. viciorice it is needless to say more than that no rational person is 

 likely to believe that the substitution of a four pointed for a single pointed 

 spine on the opercle is by itself sufiicieut to constitute a species. 



