Fresh-water Entomostraca of South America. 67 



minute examination, the value of some of them having- 

 been much disputed. A few species, on the other hand, are 

 at once recognizable, for instance, C. globosus Baird and C. 

 Barroisi Richard, the latter exhibiting in some points an 

 approach to the genus Alonella. In my aquaria I have ob- 

 served 5 different species, to be treated of below ; 2 of these 

 I regard as new to science. 



34. Chydorus Barroisi (Richard). 



(PI. XI, figs. 1, a-b). 



Pleuroxus Barroisi, Kichard, Cladocères receuillis par M. Barrois 

 en Syre et en Egypte. Revue Biol. du Nord de la France, 

 T. VI, p. 16. 



Remarks. — A detailed description of this form, 

 with figures of both sexes, has been given by the present 

 author in his paper on South African Entomostraca, and I 

 here only figure an ephippial female, to show the peculiar 

 transformation of the upper part of the carapace, and at 

 the same time to give evidence of the identity of the Bra- 

 zilian form with that found in the old world. 1 ) 



Occurrence. — Specimens of this form occurred 

 occasionally in some of my aquaria prepared with mud from 

 Sâo Paulo, and, in spite of their small size, they were 

 immediately recognized by their very rapid, jerky movements. 



Distribution. — This form was first recorded from 

 Palestine by Mr. Richard, and was subsequently raised by 

 the present author from dried mud taken at Knysna, Cape 

 Colony. It has, moreover, been recorded by Mr. Daday from 

 Ceylon. Its occurrence also in Brazil is rather interesting. 



l ) By a mistake, the curved transverse strise of the anterior part 

 of the valves have been omitted in the figure. 



