1888 ] AUSTRALIAN CLADOCEBA. 45 



ately below the anal orifice. The outer part of the tail beyond 

 this prominence is rather broad, though it gradually tapers to- 

 wards the obtuse extremity, and has the sides provided with 

 numerous tufts of very short hair; along its dorsal edge there 

 is a double row of very minute denticles, assuming upwards suc- 

 cessively the character of fine hairs. The caudal claws are re- 

 markably small and very strongly curved, each having at the 

 base a single secondary denticle. The dorsal edge of the tail 

 exhibits just above the angular prominence a slight sinus, indicat- 

 ing the place, where the anal orifice is located, and bounded 

 above by a very small projection, whence the remaining some- 

 what flexuous part of the dorsal edge becomes strengthened by 

 a thick chitinous coating. The caudal setae, issuing from a 

 small knob-like prominence at the upper part of the dorsal edge, 

 are of moderate length, distinctly Particulate and with the outer 

 joint finely ciliate. 



As usual in this family, the tail is connected to the preced- 

 ing part of the body by a distinct articulation, defined by a 

 very conspicuous transverse chitinous stripe. In front of this 

 articulation, the dorsal part of the body projects a little and as 

 a rule is closely applied against a short inner fold issuing from 

 the posterior part of the dorsal edge of the carapace, thus clos- 

 ing up the incubatory cavity behind. 



The intestinal tube exhibits the structure characteristic of 

 the Lynceidae, its anterior part, contained Avithin the head, being 

 rather dilated, but without any trace of coecal appendages, the 

 remainder, on the other hand, becoming rather narrow and form- 

 ing in the middle of the body a double loop, often however con- 

 cealed by the greatly developed ovaries. Before entering the tail, 

 the intestinal tube forms anteriorly a rounded coecal dilatation, 

 whence it immediately joins the short and muscular rectum the 

 outlet of which, as mentioned above, is at some considerable 

 distance from the extremity of the tail. 



As regards the structure of the heart and the other inner 

 organs, there is no essential difference to be noted. 



Within the incubatory cavity, or matrix, more than two 



