Fresh-water Entomostraca of South America. 87 



ephippial females (see fig. 2) the upper part of the carapace 

 is often very coarsely sculptured with rib-like, sometimes 

 anastomosing prominences, and generally assumes a very con- 

 spicuous golden yellow or orange colour. Male specimens 

 were not unfrequently met with at the time when resting 

 ova were produced by the females. 



Occurrence. — The aquaria in which this form 

 developed, were prepared with mud, partly from Itatiba, 

 partly from Argentina. 



Distribution. — Besides in Europe, this form has 

 also been recorded from North America, where also a pecu- 

 liar variety (perhaps a distinct species) has been noticed as 

 var. media (see Mr. Herrick's work). 



44. Pseudalona longirostris (Daday). 



(PI. XII, figs. 3, a— b). 



Alona longirostris. Daday, Mikroskopische Süsswasserthiere aus Cey- 

 lon, p. 34. 

 Syn. Alona macrorhyncha, Daday. 



Specific Characters. — Female. Carapace, 

 seen laterally, rounded quadrangular in form, height and length 

 about equal, dorsal margin evenly arched, ventral considerably 

 bulging in front, posterior extremity obtusely truncated, upper 

 corner distinct, lower rounded off. Head produced to an ex- 

 ceedingly elongated acute rostrum pointing somewhat obliquely 

 behind. Surface of shell sculptured with rather faint wavy 

 longitudinal lines anastomosing with each other so as to 

 form an irregular reticulation, striæ of the anterior part of 

 the valves well marked, 8 or 9 in number. Eye very small ; 

 ocellus still smaller, and about 3 times as far from the tip 

 of the rostrum as from the eye. Antennulæ comparatively 

 shorter than in the preceding species, not reaching even to 



