1888.] AUSTBALIAN CLADOCERA. 49 



have, besides the apical sensory filaments, anteriorly and some- 

 what beyond the middle, a delicate bristle, which however does 

 not originate from any knob-shaped prominence, as in the pre- 

 ceding Lynceid; they slightly project beyond the tip of the ros- 



The antennae exhibit the usual structure, and this is like- 

 wise the case with the oral parts and with the legs. 



The tail (fig. 7) is rather large, of an oblong form, and very 

 slightly tapering in its outer part, which is narrowly truncate, 

 with the anterior corner, bearing the caudal claws, somewhat 

 projecting. The ventral edge is nearly straight and strongly 

 chitinized, whereas the dorsal edge is somewhat arcuate, exhibit- 

 ing an indistinct angle below the anal orifice, and another some- 

 what more projecting angle above it. The outer part of the 

 dorsal edge is armed with very small, almost hair-like denticles, 

 arranged in two somewhat irregular rows. The upmost part of 

 this edge, above the supraanal angle is, as usual, strongly chi- 

 tinized, and exhibits close to the joint connecting the tail with 

 the body, the usual knob-like prominence, bearing the rather 

 small caudal setae. 



The dorsal part of the body in front of the tail projects 

 somewhat, as in other Lynceidae, to close up the incubatory ca- 

 vity behind, exhibiting several tufts of fine hair, that indicate 

 the edges of as many imperfectly defined segments. 



The inner organs do not exhibit any marked peculiarity in 

 their structure. 



As is the case with most other Lynceidae, more than two 

 e ggs, or embryos, are never found in the matrix, and these lie 

 invariably in juxtaposition (see fig. 6). 



The whole animal is highly pellucid, and almost colourless, 

 with only a very faint grayish tinge on the body. Also the 

 ovaries and the vitelline matter within the ova are considerably 

 paler than in most other Lynceidae, and of a very faint green- 

 ish tint. 



Biological Observations. — The present Lynceid was observed 

 at about the same time as the preceding one and in the same 



Vid.-Selsk. Forh. 1888. No. 7. 4 



