Mil. S. F. HARMKR OX THIS OCCURRENCE OF THE “ WELL-SHRIMP.” 491 
already been mentioned, some account of the genus will be found 
in Spence Bate’s ‘ Catalogue of the . . . Amphipodous Crustacea in 
the . . . British Museum’ (18G2), p. 174. A very complete sum- 
mary of the literature of Amphipoda, including the papers on 
Niphargus, is given by the Rev. T. R. R. Stebbing, at the beginning 
ol the first half of the Challenger Report on Amphipoda.* A moro 
recent paper on Subterranean Crustacea is that by A. Wrzesniowskit, 
who, besides describing a new species (p. 643) and a new variety 
(p. 655) of Niphargus, gives a list (pp. 673 — 675) of fourteen species 
which are possibly distinct, and a summary (pp. 694 — 698) of the 
geographical distribution of the Gammuridiue found in subterranean 
waters, and in the deep waters of lakes. 
A most valuable paper has even more recently been published 
by Dr. Charles Chilton,^ who emphasizes the occurrence of a huge 
system of underground waters beneath the Canterbury Plains of 
New Zealand, as a means of communication between the isolated 
localities in which the subterranean Crustacea have there been 
found; and quotes Lyell’s ‘Principles of Geology,’ in further 
evidence of the general existence of underground waters which 
would account for the distribution of these animals. 
It. has been suggested by various writers that Niphargus is, 
probably, a common animal. The object of the present communi- 
cation will have been attained, if it should direct attention to the 
examination of the fauna of ordinary wells of drinking water. 
It is probable that Niphargus may be obtained in many localities 
by the simple method of tying a muslin bag over the spouts of 
suitable taps, a device which has been successfully employed by 
Mr. W. T. Caiman in the search for Botifers, and by Professor 
Herd man § for the examination of the surface fauna of the ocean 
during an ordinary trans- Atlantic passage. 
* ‘ Zoology,’ vol. xxix. part lxvii, 1S88. 
t “ Uber drci unterirdische Gammariden,” ‘ Zeitschr. f. wiss. Zool.’, vol. 1. 
1890, p. 600. 
X “ The Subterranean Crustacea of New Zealand : with some general 
Remarks on the Fauna of Caves and Wells,” Trans. Linnean Soc., ser. 2. 
Zool. vol. vi., 1894- 97, p. 163. 
§ Brit. Association Rep., Toronto Meeting, 1897, p. 695. 
