CR USTACEAS YtiTEMA TIG EE VIE W 



291 



sac-shaped. The females carry about the fertilised eggs in a paired or unpaired 

 ovisac. Gills are wanting. Free-living or commensal Copepoda : Cyclops, Cantho- 

 <-'iiii/>tus, in freshwater; Cetochilus, Clausocalaiius (Fig. 194), marine; Notodelphys, 

 commensal in the branchial cavity of the Ascidians. Parasitic Copepoda : Corycceus, 

 X'lj'/i/iiriiia (some of which are only occasionally or temporarily parasitic), Chondra- 

 canthus, Caligus, Lerncea, Lcrnceocera, Pcnella, Lcrnanthropus, Lernceascus, Achtheres, 

 A nchorella. 



Sub-Order 2. Branchiura (Argulidse), Carp Lice. 



Body consists of the flattened shield-shaped cephalo-thorax and the small flat 

 abdomen (caudal fin) divided longitudinally. In front of the oral suctorial tube a 



0,, 



a 



<--/- sf 



Fio. 195. Argulus foliaceus young male (after Glaus). !, Anterior, . 2> posterior antenna ; pa, 

 1'iiiivil eye ; CK, unpaired eye ; r, beak or suctorial tube enclosing the mandibles and maxilke ; A/ a , 

 anterior maxillipede with the adhering disc ; 7r/ 2 , posterior maxillipede ; sd, shell glands ; (?, intes- 

 tine with its lateral branched diverticula ; &i, I)*, 63, 64, thoracic feet ; ab, abdomen ; t, testes. 



long protrusible stylet. Four pairs of long cirrus-like biramose swimming feet. Two 

 large compound lateral eyes. Testes in the caudal fin. Heart present. Females 

 without ovisacs, attach the eggs to foreign objects. Argulus (Fig. 195), on the carp. 



Order 4. Cirripedia. 



Characteristics of the attached forms : body indistinctly segmented, attached by 

 the head end, surrounded by a mantle which generally calcifies and then forms a 



