431 



Synopsis of the known Species of British Fresh-water 



Entomostraca. 



Part I. Cladocera. 

 By D. J. ScouRFiELD, F.R.M.S. 



{Read January IGth, 1903.) 



Plate 24. 



Now that we have such an excellent and authoritative work 

 ■on the Cladocera as Lilljeborg's " Cladocera Sueciae," * it seems 

 desirable that a list of the known British species should be drawn 

 up, so that those interested in these creatures may have some 

 guide (1) to the species described and figured therein which have 

 been found here, and (2) to the very few^ forms that are known 

 to be British, but are not referred to by Lilljeborg. 



In the case of the latter species short descriptions and figures 

 will be given, thus supplementing the work of Lilljeborg, so far 

 as is necessary for our purpose, and putting into the hands of 

 those possessing, or having access to, the "Cladocera Sueciae" 

 a complete synopsis of the Cladoceran fauna of the British 

 Isles as known at present. 



This arrangement is, to be sure, not to be compared with the 

 issue of a good monograph on our British species ; but there is 

 this advantage about it, that British students, by having to 

 constantly refer to the " Cladocera Sueciae," will be kept on the 

 watch for some of the species recorded as Swedish that have not 

 so far been taken in this country. 



It is not considered necessary to give descriptions of the species 

 to be found in the "Cladocera Sueciae,""or even keys for their 

 identification, as this has been so well done in the book referred 

 to. An attempt will, however, be made to indicate the synonyms 

 under which the species have been recorded in different works 

 on British Entomostraca. In the case of the rarer species the 



* " Cladocera Sueciae oder Beitrage zur Kenntniss der in Schweden 

 lebenden Krebsthiere von der Ordnung der Branchiopoden und der 

 Unterordnung der Cladoceren." By Wilhelm Lilljeborg. Upsala, 1900. 



