COPEPODA 



375 



Chondracanthus (Fig. 252), which infests the gills of various marine 

 fishes, has in the adult stage a large female, whose body is produced 

 into irregular, paired lobes and her appendages degenerate, though 

 the mouth has not a proboscis but is flanked by the three pairs of 

 minute, sickle-shaped jaws. The males are small, retain more of the 



Fig. 252. 



Fig. 252. Chondracanthus gibb OS us . After Claus, A, Female. B, Male, more 

 highly magnified, al. alimientary canal; an.' antennule; an." antenna; e. eye; 

 e.s. egg " sac " ; nixp. maxilliped ; t. testis ; th. 2 and 3, thoracic limbs ; vas d. vas 

 deferens; cJ, males attached to females. 



Fig. 253. Stages in the life history of Lernaea. A, Metanauplius. B, First 

 Cyclops stage. C, "Pupa". D, Sexual stage: coition. E, Ripe female. 

 an.' antennule; an." antenna ; ^z a;, secretion of a gland by which fixation is 

 effected ; hd.pr. processes of the head of the female which are imbedded in the 

 tissues of the host; mxp. maxilliped; sip. siphon; th.z, second thoracic limb; 

 ram. ramus of caudal fork. 



copepod organization than the female, and cling by hook-like 

 antennae to her body. 



Caligus, ectoparasitic, mainly in the gill chambers of fishes, is 

 clumsily built and has a suctorial proboscis, but retains the power of 

 swimming. Its sexes do not differ greatly. 



Lernaea (Fig. 253) hatches as a Nauplius and at the first Cyclops 



