74 
MEMO IBS OF TEE QUEENSLAND MUSEUM. 
worth requoting here. He writes: — v ‘ It is most singular that this species,* 
with the Blackfish ( Gadopsis marmoratus ) should be identical with species found 
abundantly in Victorian Rivers, and wholly absent in all the southern waters of 
Tasmania. The Unio ( U . moretonicus) , and the Freshwater Lobster ( Astacopsis 
Franklinii ), are also restricted to the rivers which discharge their waters into 
Bass’s Straits. The peculiar inhabitants of northern rivers, therefore, are more 
Victorian than South Tasmanian in character, which is remarkable when we 
consider the present insular character of Tasmania. ”f And again — Cf The 
Blackfish, whose singular distribution has been commented upon, is found in 
nearly all the rivers of Tasmania which flow into Bass’s Straits. Their original 
absence in some northern streams, such as the South Esk, is somewhat puzzling, 
but the total absence from all the other rivers and streams of Tasmania where 
the conditions are identical can only be explained on the principles of 
geographical distribution as illustrated by Darwin and Wallace.” In 1893 the 
author took exception to the last sentence in the following words, with which he 
sees no reason now to differ “With the latter part of this quotation we can not 
agree, and we think the solution of the ‘ puzzle ’ will be found in the different 
character of the geological formations through which the streams flow, or the 
different composition of the water constituting such streams.” As somewhat 
confirming this view Johnston’s remark, that in the North Esk they fail to attain 
to the size found commonly in the other streams of Northern Tasmania, tells 
against him, for it seems probable that the conditions of life in that stream had 
a deleterious effect on the fish, which in its southern namesake had become so 
accentuated as to preclude its very existence in a natural state. Tenison Woods 
is, I believe, the earliest writer to extend its range to the western waters of New 
South Wales, alluding to it as “a very common fish in some of our rivers both 
of eastern and western waters”; but this is merely a general assertion, no locality 
being mentioned, and must, therefore, be taken for what it is worth 4 Maeleay, 
however, in 1885 definitely fixed a western habitat by placing on record his 
acquisition of a specimen from the Little River, a tributary of the Murrumbidgee 
near Yass. In the previous year Steindaehner made another attempt to differen- 
tiate from G. marmoratus the dull-colored form, peculiar to lagunes and bayous, 
* L$i the Bass ( Percolates colonorum). 
t This restricted Tasmanian distribution was first noticed by Mr. Morton Allport, who 
in May, 1867, read a paper before the Royal Society of Tasmania ’“On the Local Distribution 
ot some asmarnan Animals (Proe. Roy. Soe. Tas., 1867, pp. 9 to 13), in which the following 
paragraph occurs (p, 10) — “ The large fresh-water fish known to northern colonists as the 
Black-Fish/ and the great river Crayfish, abound in streams flowing to the northern and 
western coasts, and are wanting in those flowing to the eastern and southern. ’ ’ 
J Since writing this paragraph I find that Woods 7 announcement was forestalled by 
the Report of the Royal Commission on the Fisheries of New South Wales, 1880. in which the 
following passage occurs: — “ The ‘ black-fisli 7 ( Gadopsis marmoratus ) is a remarkable-looking 
fish, which is found in all these rivers [i.e., those of the Murray River system] ; it is a mud 
fisli, and is seldom caught except by the emptying or drying-up of a waterhole. It is said to 
be good, and to attain a length of 16% inches. 77 My comment, appended above to Woods r 
record, is equally applicable in this case. 
