566 FRESHWATER ENTOMOSTRACA OF N.S.W. ii. COPEPODA^ 



Female. Cephalotliorax somewhat more robust than the preceding species; 

 first segment much longer than the four succeeding segments combined; last seg- 

 ment with the lateral parts produced, bearing stiff haii-s. Abdomen equal to two- 

 thirds of the cephalothorax in length, genital segment longer than the combined 

 length of the two succeeding segments, slightly dilated at the base; caudal rami 

 much longer than in the two preceding species, narrow, slightly divergent. An- 

 tennules short and thick, composed of eight segments. Natatory legs similar to 

 those of P. phaleratus. Fifth pair composed of a smaU lamella, bearing a com- 

 pai-atively short spine and two slender setae. Length, . 9 mm. 



Distribution. — N.S.W. : Kendall, Five Dock, Centennial Park; New Guinea; 

 Hawaii; Ceylon; North and South America; Europe. 



Division 3. HAEPACTICOIDA. 



Body slender, more or less cylindrical, no distinct demarcation between the 

 cephalothorax and abdomen. Last segment of the cephalothorax articulates with 

 the preceding segment and is firmly attached to the first abdominal segment. 

 Antennules small, rarely more than eight segments, both prehensile in the male. 

 First pair of legs either similar to the succeeding pairs or transformed into grasp- 

 ing organs; three succeeding pairs natatory; fifth pair reduced, never natatory. 

 Heart absent. Ova in a single ovisac attached ventrally or, more rarely, in two 

 ovisacs. 



The great majority of freshwater Harpacticids belong to the Canthocamp- 

 tidae and this is the only family represented in Australia. This is the first re- 

 cord of the presence of .members of this division in New South Wales. 



Family CANTHOCAMPTIDAE. 



Rostrum very small. Antennules usually composed of eight segments though 

 the number may be reduced, distinctly hinged in the male. First pair of legs 

 more or less prehensile, endopodites usually longer than exopodites; three suc- 

 ceeding pairs with exopodites always longer than endopodites which are some- 

 times reduced; fifth pair in the female more or less lamellar with the distal seg- 

 ment well defined and the proximal segment expanded inside. A single ovisac 

 present. 



This family comprises four genera that include true freshwater forms; two 

 of them are represented in New South Wales. 



Key to genera of Canthocamptidae. 



A. Antennules composed of S segments. 



• B. Endopodites of the 2nd and 3rd pairs of legs composed of three segments. 



Canthoca»iptii». 



BB. Endopodites of 2nd and 3rd pairs composed of two segments 



Attheyella. 

 AA. Antennules composed of less than 8 segments. 



B. Antennules 7-segmented Moraria. 



BB. Antennules 6-segmented Marshia. 



Genus Attheyella Brady, 1880. 



Body slender, cephalothorax very little broader than the abdomen. Rostrum 

 very small. Antennules comparatively short, eight-segmented. Antennae with 

 the basal portion not subdivided, exopodite generally one-segmented, bearing two 

 apical and two lateral setae. First pair of legs imperfectly prehensile, endo- 



