84 ME. GEOFFREY WATKIN SMITH ON THE 



continuous row of bristles fringing the whole posterior region of the body ; posteriorly 

 in the neighbourhood of the dorsal setae these bristles become strong and spiniform. 

 There is a distinct indentation in the contour of the hind region of the body. 



The dorsal seta? are unique in structure, in that they end in a bunch of simple non- 

 plumose bristles. 



Length -4 mm. 



Colour. Green. 



Occurrence. Among weed in Lake Dulverton. No males observed. 



Family Ltnceidj:. 



Genus Alonella (Sars). 



This genus and the related Alona and Dunhevedia appear to be abundantly represented 

 in Southern Australian waters. 



Alonella nasuta, sp. n. (PI. 16. fig. 4.) 



Form of the carapace is regularly oval without any marked angles. The usual 

 striations and ventral fringe of setae are present. 



The head is drawn out into an exceedingly long and tapering nose, which projects far 

 beyond the end of the first antennas. 



The first and second antenna? are normal in structure and do not call for any special 

 remark. 



The anal spines are long and furnished at the base with one strong spine and several 

 bristles. On the telson are four stout short spines, and then follow about five groups of 

 bristles. Beyond these bristles comes a marked concavity, and the margin is continued 

 rather sinuously to the dorsal setae (PI. 16. fig. 5). 



Length 5 mm. 



Colour. Yellow. 



Occurrence. Among thick weed in Lake Dulverton. No males observed. 



Alonella pkopinqua, sp. n. (PI. 16. fig. 6.) 



The carapace is rather square-shaped, but without any distinctly marked angles. It 

 is fringed ventrally with setae, and the striae on the carapace are densely broken up into 

 roughly quadrangular blocks. 



The head is drawn out into a moderately long proboscis ; but both the first and 

 second antennae project nearly as far as the proboscis, thus differing from A. nasuta. 



The appendages do not offer any characters of specific importance. 



The anal claws are long and furnished each with a single strong spine at its base. 



The telson rises abruptly above the anal claws and is furnished with a row of 9 lateral 

 fairly stout spines, behind which are one or two very small bristles of insignificant 

 appearance. Between the end of the spine-row and the dorsal setae the back is smooth 

 and rises to a prominence, about midway (PI. 16. fig. 7). 



Length - 35 mm. 



Colour. Yellow. 



Occurrence. Among thick weed in freshwater lagoon near Adventure Bay. 



