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4. The Fresh-water Entomostraca of Cape Province ( Union of South 

 Africa). ~By Gr. O. SARS. Part I: Cladocera. With 13 plates. 



(Plates XXIX-XLI.) 

 INTRODUCTION. 



UNDER the above title I intend to give an account of all the forms of 

 fresh-water Entomostraca from Cape Colony, which have as yet come 

 under my notice, with short descriptions and easily recognisable figures 

 of each species. The present part only deals with the Cladocera ; in two 

 or three succeeding parts the Ostracoda and Copepoda will be treated 

 of in a similar manner. 



In the General Catalogue of South African Crustacea published by 

 the Rev. T. R. R. Stebbing in the present Annals, vol. vi, nineteen 

 species of Cladocera are enumerated. Nine of these had been described 

 by the present author in a previous paper * from specimens raised out 

 of dried mud from Knysna, and in another paper f two other species 

 belonging to the Fauna of Sumatra were also stated to occur in Cape 

 Colony. The remaining eight species have been recorded chiefly by 

 Prof. Brady from the neighbourhood of Natal. In the present paper 

 more than twice as many species, viz. forty-three, will be described as 

 belonging to the Fauna of Cape Colony, eleven of which are apparently 

 new to science. 



The greater number of the forms here treated of have been reared 

 from dried mud in my aquaria, and have been domesticated for several 

 years and in numerous successive generations. I have thereby been 

 enabled to subject the said species to a very thorough investigation, 

 and at the same time to give good and characteristic figures of them, 

 representing the animals as they appear in the fresh and living state. The 

 great advantage attained by this method for the study of exotic fresh- 

 water Entomostraca will be easily appreciated. For thereby not only will,. 

 as a rule, a sufficient number of specimens of each species be obtained 

 for examination and comparison, but this method permits the study of 

 the biological relations of the species, their growth, movements, propaga- 

 tion, and seasonal variation. Especially as regards the Cladocera, the 



* On some South African Entomostraca raised from dried mud. Chr. Vid. 

 Selsk. Skrifter f. 1895. 



f Fresh-water Entomostraca from China and Sumatra. Arch. f. Mathem. 

 u. Naturv. 1903. 



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