160 MR. LiEOFFEKY SMITH UN THE 



Note. — Nobili, in his pivper iu the ' Auuali del Museo Civico di 

 Geneva, * voh xl. p. 244, 19U1, describes a specimen of Astacopsis 

 identical with Milne-Edwards's A. australiensis, as coming from 

 Sorong, New Guinea. The occurrence of an Astacopsis in New 

 Guinea is so utterly at variance with all the known facts of 

 the distribution of Australian Crayfishes that I am unable to 

 accept the locality of this single specimen as correct, especially as 

 all the subsequent expeditions to New Guinea have failed to find 

 any Astacopsis there, although Chceraps in abundfinee have been 

 obtained. Dr. Caiman has suggested to me that Sorong was 

 probably wrongly I'ead for Sydney, or else that the label for this 

 specimen had been somehow transposed. Until further evidence 

 is forthcoming as to the oecuiTence of an Astacopsis in New 

 Guinea, the locality given for this single specimen, which is 

 identical with the small Paramatta form of A. serratus, must be 

 received with the greatest scepticism. 



Remarks on the above species. — For including all the above forms 

 under one species, A. set^ratus^ ranging from the Murray River 

 to Sydney, I shall be blamed by many systematists, but the 

 problem is one of peculiar difficulty. The Freshwater Cray- 

 fishes, like so many of the large Decapods, begin breeding long 

 before they have attained their limit of size ; we are therefore 

 often puzzled to know whether a particular set of specimens 

 represents a separate species, or only not fully-grown individuals 

 of a species which progressively alters as it grows older. It 

 seems undoubted that the large Murray Rivei' and the Para- 

 inatta River Crayfishes are identical. It is true that the 

 geographical separation of the Murray and Paramatta is not so 

 great as it looks, a.s the Lachlan River, a tributary of the Murray, 

 iises in the Blue Mountains on the other side of the watershed 

 to that on which the Paramatta rises. The Yarra, Bunyip, 

 a.nd other rivers of the Victorian Highlands are similarly 

 •divided from the Murray tributaries, and here, although the 

 differences are veiy slight, it may be possible to separate a true 

 variety of Crayfish inhabiting these rivers from the Murray 

 River form. The small Blue-Mountain Crayfish bears much the 

 same relation to the big Paramatta form as the small Tas- 

 xnanian Crayfish to the big one. 



Unlike the genera Chceraps and Engmus, they are not known to 

 leave the water and migrate a.cross the land, so that the various 

 races of this species must have been isolated from one another 

 for very long period's. 



Astacopsis kebshawi, sp. n. (Pla. XIX., XX.) 



The Large Gippsland'CrdyHsh. (PI. XIX.) 



The ro£;trum is broader than in ^4. serratus, with blunter 

 ■tuberculated spines on its keels, thus approaching A.franklinii. 



The spines on the carapace are replaced by blunt, rounded 

 tubercles and ridges.. Similarly., the sharp spines present on the 



