1895-^0.8. SOUTH- AFRICAN ENTOMOSTRACA. 2 1 



cases it has an appearance as if some additional series of denticles were pre- 

 sent; but, on a closer examination, it maybe easily seen, that this is only 

 due to the individual being about to cast its skin, the apparent additional 

 denticles belonging, in reality, to the underlying new skin in process of forma- 

 tion. The double spine-rows occupy about the distal half of the tail, its upper 

 part having only, at some distance from the edge on each side, a single 

 series of short straight denticles. Close to the very movable articulation 

 connecting che tail with the adjoining part of the body, occiu-s posterioriy 

 a small tubercle carrying the caudal setae, and, at a short distance below 

 this tubercle, the posterior edge forms a very slight angular prominence, 

 representing the postanal angle. The terminal claws are rather slender 

 and but slightly cur\'ed, being quite smooth, without any trace of a basal 

 denticle. 



The alimentary- tube is rather wide in its anterior part, and here 

 generally filled with yellowish orange contents. Posterioriy it forms, as 

 usual in the Lvnceidæ. a nearly double wind, and has the contents ^-ery 

 dark. Before joining the short, muscular rectum, it forms a considerable 

 dilatation, but wants any tnie coecal appendage. The anal orifice is found 

 at a short distance below the base of the tail dorsally. 



The Ovaria are often very conspicuous, shining through the shell as 

 2 rather broad dark green masses, partly covering the intestine laterally. 



In the matrix, generally only a single ovum or embryo is found, more 

 rarely two, and in this case, owing to the inconsiderable width of the 

 matrix, arranged the one in front of the other. 



The adult male (fig. 3) is much smaller than the female, scarcely 

 exceeding in length ^^mm. It somewhat resembles in form, yoimg female 

 specimens, but has the head more erect, and is, moreover, at once disting- 

 uished by the structure of the antennulae, the ist pair of legs, and the tail. 



The antennulæ are scarcely longer, but much thicker than in the 

 female, and have the olfactory papillae more fully developed, extending 

 considerably be^■ond the tip of the rostrum. 



The ist pair of legs are each armed with an exceedingly large, 

 anteriorly airving hook, which is horn-coloured and generally projects 

 beyond the valves. 



The tail (fig. 4) is considerably narrower than in the female, being but 

 very slightly expanded distally. The lateral spines are fewer in number, and 

 restricted to the outer third part of the tail only, though, as in the female, 

 arranged in a double series on each side. The terminal claws are com- 

 paratively shorter, and, in front of them, there proceed from the tip of the tail 

 2 peculiar soft, cylindrical appendages, constituting the outer sexual organs. 



