OR USTA GEA—S I'.S TEMA TIC BE VIE TV 



289 



Sub-Order 2. Cladooera (Daphnidse), Water Fleas. 



Body small, with few indistinct segments and 4 to 6 pairs of swimming feet The 

 posterior antennje are large rowing feet. 



Fig. 102.— Daplmla similis, young female (after Glaus), ai, Anteniuile ; no, second (rowing) 

 antenna; Z, hepatic cjecum ; aw, eye; d, intestine; sei, shell gland; /t, heart: bru, brood' cavity ; 

 a&, abdomen ; 6r, branchial sac ; /j-Zg, trunk feet ; fir, brain. 



Fig. 193. — Oypridina medlterranea, female, from the side (after Glaus), ax. Anterior, ao, 

 posterior antenna; ; /s, frontal organ ; oc, unpaired eye ; ok, paired eye ; 7i, heart ; m, stomach ; s, 

 shell ; /2, cleaning foot ; ff, sexual organs (!) ; /i, first foot ; mj^, second maxilla ; sm, shell muscle, 

 mail, first maxilla ; o6, upper lip ; md, mandible. 



Branchial sacs may be wanting. With bivalve shell. Head freely projecting. 

 Female with dorsal brood cavity between shell and trunk. Heart sac-shaped with 

 VOL. I U 



