40 MARGUERITE HENRY. 



recorded from Centennial Park and the Waterloo Swamps, 

 Sydney. 



Leptocyclops viridis, sp. n. 



(Plate II, figs. 8, 9). 

 This is a very small form; the length of the adult female 

 only attains 0*61 mm. 



The cephalothorax is moderately slender and oval in 

 outline; the greatest width occurs about the middle. The 

 abdomen is slender and composed of four segments; the 

 genital segment is not dilated and is equal in length to the 

 next two segments combined. The caudal rami are some- 

 what divergent, slightly longer than the last segment. The 

 inner of the two middle apical setse is twice as long as the 

 outer; the seta of the inner corner is small, shorter than 

 that of the outer. 



The antennules are long and slender, reaching, when 

 reflexed, almost to the end of the cephalothorax. They 

 are composed of twelve segments, the third and sixth of 

 which are very small, the last six are slender and elongated. 

 The rudimentary palp of the mandible bears, two long 

 feathered setse and a bristle. 



The anterior maxillipedes have the subdivision of the first 

 basal segment indistinct. The posterior maxillipedes have 

 stout curved setae on the proximal segment. 



The natatory legs are well developed with tri-articulate 

 rami. The first pair is the smallest, and has the second 

 basal joint produced at the inner corner and provided with 

 a spine. The apical spines of the fourth pair are particularly 

 long. The last pair (fig. 9) is very small, it consists of a 

 simple lamella armed inside with a denticulate spine and 

 outside and at the tip with a slender seta. Ovisacs oval 

 in shape and greyish-brown in colour. 



The male is smaller than the female and possesses very 

 much swollen and curved antennules. 



