The Fresh-water Entomostraca of Cape Province. 319 



Occurrence. Some specimens of this form developed in oue of 

 my aquaria, and at once attracted my attention by their bright red 

 colour and comparatively slow movements. The mud with which the 

 aquarium was prepared was derived from a small pool in the Cape 

 Flats, and kindly sent to me by Dr. Purcell. 



Distribution. Throughout Europe, Turkestan, Madagascar, Aus- 

 tralia. 



17. CERIODAPHNIA RIGAUDI, Richard. 

 (Plate XXXIV, figs. 3, 3 a, 6.) 



Ceriodaphnia rigaudi, Richard. Sur quelques animaux iuferieurs 

 des eaux douces de Tonkin. Mem. Soc. Zool. de France, t. vii, 1894, 

 p. 239. 



Specific Characters Female. Carapace, seen laterally, more or less 

 rounded in outline, with the posterior protuberance only slightly pro- 

 duced, and occurring somewhat above the axis of the body. Head 

 rather procumbent, with the frontal part rounded anteriorly and 

 produced below to a very conspicuous acuminate rostrum pointing 

 obliquely downwards. Reticulation of the shell rather coarse, edges 

 of valves smooth. Eye comparatively large, with very distinct refract- 

 ing bodies. Anteunulae of the usual structure, not nearly exteudim; 

 to the end of the rostrum. Tail-piece moderately broad and obliquely 

 truncated at the end ; anal denticles rather thin, six to eight on each 

 side ; apical claws smooth. 



Body semipellucid, with a more or less distinct reddish or orange tinge, 



Length of shell scarcely exceeding (X55 mm. 



Remarks. This form, first described by Dr. Richard, is the smallest 

 of the known species, and is, moreover, at once recognisable by the 

 acuminate beak-like projection issuing from the head below. Th( v 

 form described by the present author from Australia as C. cornuta 

 is regarded by Dr. Richard as only a variety of the present species. 



Occurrence. Numerous specimens of this characteristic form were 

 reared by me in the year 189-5 from the Knysua mud. It also occurred 

 in an alcoholic sample taken by Dr. Purcell from a dam at Faure, near 

 Cape Town, and kindly sent to me for examination. 



Distribution. Tonkin, Palestine, Sumatra, Ceylon, New Guinea, 

 Australia. 



GEN. 5. MOINA, Baird. 



Remarks. By the rather fully developed and mobile autenuulae, 

 this genus exhibits a certain approach to the next family, the Macro- 

 thricidae ; but the structure of the legs is very different, and on the 



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