FRESHWATER CRUSTACEA OP TASMANIA. 83 



BOSMINA BREVIROSTRIS, Sp. n. (PI. 16. fig. 1.) 



Female. — The carapace is more elongated than in B. rotunda and the posterior angle 

 is distinctly marked. A seta is present on each valve close to the posterior spine. 



There is a slight projection where the forehead passes into the first antennae. 



The first antennae are short, slightly curved, and with about 8 joints below the 

 antennal spine and sensory seta?. 



The second antenna) are short and do not project as far as the anterior angle of the 

 valves of the carapace. 



The anal claws are rather short and carry about six small spines, which extend nearly 

 to the tip of the claws. 



Length 5 mm. 



Colour. Green. 



Occurrence. In the plankton of the Great Lake. No males were observed. 



BOSMINA SOBJBLLI. (PI. 16. fig. 2.) 



Female. — This very small species has the carapace elongated and sloping rather 

 suddenly to the posterior angle from the dorsal surface; the angle is well marked. 



There is practically no projection where the forehead passes into the first antenna}. 



The first antenna) are long with about 11 joints below the antennal spine and sensory 

 seta). 



The second antenna) are short and do not project as far as the anterior angle of the 

 valves of the carapace. 



The anal claws are long, with about 4 spines near their base. 



Length "35 mm. 



Colour. Green. 



Occurrence. In the plankton of Lake Sorell. No males were observed. 



Family Lyncodapiinidje. 



Genus Macrotiirix (Baird). 

 Sars (Forhand. Christiania, 1885 ) has described M. spinoaa from Australia. 



Macroturix burstalis, sp. n. (PI. 16. fig. 3 ) 



The carapace is oval in shape, with the posterior angle rounded and situated rather 

 dorsally. 



The ventral margin of the carapace is fringed with exceedingly long and conspicuous 

 setae. 



There is practically no constriction between head and thorax. 



The first antennae arc not dilated at the end, are tipped with a few very long seta;, 

 and carry about 8 short spines on their stems interiorly. 



The second antennae have the normal structure ; the compound setae arc very long 

 and all subequal in length. 



The anal claws are rather small and simple, without spines ; behind them is a 



