[Read before the Philosophical Institute of Canterbury, 6th December, 1905.]
In my paper on the subterranean Crustacea of New Zealand published in 1894 (Trans. Linn. Soc., vi), when discussing various questions in connection with the three species of Phreatoicus known at that time, I said, “The questions suggested may perhaps be some day solved by the discovery of species of Phreatoicus still living above ground in the mountain-streams of the Southern Alps, places where very littel search of the kind required has hitherto been made” (l.c., p. 202). I am not sure that the questions under consideration are very much nearer solution now than they were then, and certainly no species of Phreatoicus has yet been found among our Southern Alps; but in making the statement quoted I little anticipated that within the next twelve years so many species would be found in other places.
At that time there was known only the one genus, with three species—two found underground in New Zealand, and the third on the Mount Kosciusko plateau, in Australia. Now, thanks to the researches of Mr. G. M. Thomson, Professor Baldwin Spencer, Mr. T. S. Hall, and particularly of Mr. O. A. Sayce, we are acquainted with five species of the genus Phreatoicus, and with no less than three other closely allied genera, each with one species. All these additional forms, however, were from Australia and Tasmania, and up to 1902 no surface form had been recorded from New Zealand. In that year, however, Mr. (now Professor) H. B. Kirk brought me specimens of a Phreatoicus found in a fresh-water lagoon in Ruapuke Island, in Foveaux Strait. These were exhibited at a meeting of the Philosophical Institute of Canterbury on the 26th November, 1902 (see Proc. N.Z. Inst., xxxv, p. 564), but no description has as yet been published. In the present year (1905) specimens of the same genus were found at Mosgiel, and afterwards at Woodhaugh, both places being near Dunedin. These have been very kindly handed over to me for examination by Mr. G. M. Thomson.
The occurrence of the species at Woodhaugh reminds us how little we really know of the smaller animals even of places that have been fairly well searched, for Mr. Thomson and myself, and probably many others, have made many collections from this locality without coming across the species in question, although it is by no means a particularly small one, some of
the specimens being nearly 1 in. in length. Judging from Mr. Sayce's experience in Australia, it is quite probable that other forms are still to be found from the streams and fresh waters of New Zealand, and I shall be grateful to any collectors who will send me any shrimp-like creatures they may find under stones. or in moss in such situtations.
From the description given below it will be seen that the species now to be described, though found in surface waters, is a blind one, and that it is whitish in colour, in these respects resembling the two subterranean species occurring in the underground waters of the Canterbury Plains.