Phyllopoda of Australia. 227 



PAGE.. 



22. Estheria dictyon, E. 255 



23. Cyclestheria hislopi, T., and India - - - 256 



Lynceidae. 



24. Lynceus macleayana, B.E. - - . - _ 258 



25. „ tatei, B. - - - - - 258 



26. „ eremia, E. - - - - - 258 



Sub-order Phyllopoda. 



Entomostraca of various shapes, with or without a carapace or 

 shell ; the possessors either having it fashioned as a dorsal 

 shield, or in the form of two large valves enveloping the entire 

 animal. Eyes sometimes pedunculated, sometimes sessile- 

 Ocellus (simple eye) present. All the appendages placed behind 

 the mouth parts respiratory, of approximately uniforna structure- 

 and leaf-like form ; their number very variable, 10-63-. (This- 

 description does not include the Cladocera). 



Re/narks. — Prof. G. O. Sars has divided this sub-order into 

 three groups. They are of widely separated types, those without 

 any carapace or shell (Anosti'aca), those with a large chitinoua 

 shield arching over the back, which in outline is of horseshoe 

 shape (Notostraca), and those with the body surrounded by a 

 large chitinous bivalve shell, connected dorsally, and capable of 

 being opened or shut by the aid of powerful adductor muscles, 

 so that the animal may be entirely enclosed. — (Conchostraca). 



None are marine inhabitants, and, with the exception of but 

 very few forms which live in salt inland waters, are only found 

 in fresh water, and usually in quiet shallow lakes or pools (often 

 less than a yard acro.ss), which completely dry up periodically. 

 They range in length from a quarter inch to three inches. 



Their growth is often surprisingly rapid ; Messrs. Spencer and 

 Hall mention in the Report of the Horn Expedition to Central 

 Australia that in only a few days after a fall of rain numberless 

 specimens of Apus, measuring 2\ inches in length, were seen 

 swimming about the rain pools which could only have come from 

 eggs. Probably the high temperature of the water is a stimulus, 

 for this strikingly rapid development. 



