Art. XVI I. — Niphargus iiulchellus, a New Victorian 

 Blind Amph'ipod. 



By O. a. SAYCE. 



(With Plates XV., XVI.) 

 [Eead 16th November, 1899.] 



In a previous paper published in this journal (present volume, 

 p. 122), I described and figured a blind Isopod, Phreatoicoides 

 gracilis^ from a fresh-water runnel in Gippsland. In a small 

 pool, within a few yards from this runnel, I collected three 

 specimens of a blind Amphipod, which, upon examination I find 

 to possess characters in common with the genus Niphargus of 

 Schiodte. This genus is described by Bate and Westwood,^ with 

 which the present species agrees in all respects except in the 

 terminal uropoda, which do not possess a rudimentary inner 

 ramus. This slight modification of structure is, howevei', a 

 minor feature, and I have, therefore, considered it a Niphargus. 



The Niphargi are of particular interest, and live generally in 

 closed pump-wells in England, and many parts of Europe, where 

 some species inhabit lakes. Their nearest congener is said by Bate 

 and Westwood to be Eriopus, from the deep sea off Bohusia. 



In 1892 Mr. G. M. Thomson described two forms from 

 Tasmania, which with some hesitation he placed in the genus 

 Niphargus, viz., N. mortoni and N. inonianus} Of the two, the 

 latter species, from the summit of Mount Wellington (4,000ft.), 

 is the nearest to the normal type. The present species is well 

 characterised, and differs from N'. mo7ita7ius by the more slender 

 body, narrower side-plates, the want of eyes, the elongated last 

 pereiopoda, and the greatly extended, unibranched, jointed, 

 terminal uropoda ; these are longer than in any figures of 

 amphipods that I have seen, and bear, on microscopical evidence, 

 numerous specialized sensory setje. 



1 A History of British Sessile-eyed Crustacea, by C. Spence Bate, F.R.S., F.L.S., and 

 J. O. Westwood, M.A., F.L.S., Vol. I., p. 311. 



2 Notes on Tasnianian Crustacea, with Descriptions of New Species, by G. M. Thomson, 

 F.L.S. Proc. Uoyal Soc. Tasmania, 1802, ji. 68. 



