l89=;. Xo. 8. SOUTH-AFRICAN ENTOMOSTRACA. 39 



greatest ainature somewhat behind the oailar region, and also the ventral 

 margin exliibits, behind the middle, a distinct convexity-, whereas, in front 

 of the middle, a very shallow sinus occurs. The anterior extremity is 

 broadly rounded, the posterior one, on the other hand, tapers gradually 

 to an obtuse point extending nearly in the longitudinal axis of the shell. 



Seen from above 'fig. i b), the shell exhibits an oblong oval form, 

 with the greatest width about equalling half the length, and ocairring 

 behind the middle. Both extremities appear somewhat blunted, the an- 

 terior one being, however, a little narrower than the posterior. 



The valves are rather thin and somewhat unequal, the left one being 

 the larger and overlapping the right anteriorly, as well as along the ventral 

 face, whereas, at the posterior extremity, it is slightly overlapped b}- the 

 right one. Anteriorly, both A'alves form a thin hyalin border, which is 

 somewhat broader on the left valve, and also, along the posterior part of 

 the ventral face a similar narrow border may be traced. The inner dupli- 

 catures of the valves (see, fig. i e) are not particularly broad, that of the 

 anterior extremity- being, as usual, more fully developed than that of the 

 posterior. 



The surface of tlie shell is quite smooth, without any perceptible 

 sculpturing, and only provided with scattered delicate hairs towards each 

 extremity. The musailar pits in the centre of each valve are pretty con- 

 spicuous, and of an appearance similar to that found in the genus Cypris. 



The eye is rather large, and easily obser^-able through tlie shell, 

 being placed as usual. 



The several limbs nearly agree in their structure with those in the 

 genus Cypris (see fig. i e). 



As in that genus, the nafator}- setæ on the antennæ are rather elon- 

 gated, those of the inferior antennæ extending until the tips of the ter- 

 minal claws. 



The masticator}- lobes, and palp of the ist pair of maxillae ^^fig. i f) 

 likewise agree with those in the typical species of Cypris in being ver\- 

 narrow and digitiform. 



The 3nd pair of maxillae have each a distinct branchial plate fringed 

 with 5 plumous setae ^see fig. 1 g). 



The 2 pairs of legs (see fig. i e' do not differ materially in their 

 structure from those in the genus Cypris. 



The caudal rami, on the other hand, are highly distinguished b}- their 

 powerful development, and, in accordance therewith, the posterior part of 

 the body appears also unusually much produced and strongly muscular, 

 being strengthened on each side by a very conspicuous, horn-coloured 



