416 Notes on the Crustacean Fauna of the English Lakes. 



NOTES ON THE CRUSTACEAN FAUNA OF THE 

 ENGLISH LAKES. 



EY GEORGE STEWARDSON BRADY, M.R.C.S., C.M.Z.S. 

 (With a Plate.) 



Having, during several short rambles amongst the mountains of 

 Cumberland and Westmoreland, paid considerable attention to 

 the microscopic Crustacea which inhabit the numerous lakes and 

 tarns of that district, I propose, in the following pages, to 

 offer a few remarks relative chiefly to the distribution and 

 habitat of the various species, and also to describe briefly two 

 or three new or little-known forms. And though I take the 

 group known as the English lakes, 'par excellence, for the 

 groundwork of my remarks, I shall also include therein to 

 some extent the lakes of Northumberland, Dumfriesshire, 

 Selkirkshire, and Kirkcudbrightshire, amongst which I have 

 spent many pleasant days with net and collecting bottles. 

 The lakes included in this programme may indeed be looked 

 upon as forming in themselves a pretty well-defined group 

 intermediate between those of the Scottish Highlands on the 

 one hand, and of the Southern English Lowlands on the other. 

 Whether the Crustacea of the more northern Scottish waters 

 differ materially from those of the south cannot now be stated, 

 as they have yet received scarcely any attention ; but from all 

 that we know of the lacustrine Crustacea of the English 

 Lowlands, it may confidently be asserted that the difference is 

 here very great indeed. 



And it may be interesting to tourists with a love for 

 natural history (but who begin to find the geology, botany, 

 and mineralogy of our islands worn somewhat threadbare, so 

 far as the discovery of new things is concerned) to know that 

 the microscopic Crustacea of our ponds and lakes, and especially 

 of mountain lakes, are sure to afford novelties to the diligent 

 observer for many a year to come. Not that the discovery of 

 new species ought to be the chief ambition of the naturalist, 

 nor that even this may not yet be done by the hard-working 

 botanist or geologist ; but there is, nevertheless, a legitimate 

 pleasure in discovering and describing forms of life which have 

 been hitherto unknown; and in no branch of investigation are 

 we, perhaps, more likely to find it, than in that of which wo 

 are here treating. 



The higher groups of Crustacea (Amphipoda andlsopoda), 

 which are abundantly represented in lowland ponds and 

 streams by such creatures as Gammarus pulex and Asellus 

 aquaticus — animals of the sandhopper and woodlouse type — ■ 

 are scarcely to be found in mountain lakes, though we occa- 

 sionally meet with them in very small bog-pools on the hill- 



