154 



SYSTEMATIC ZOOLOGY 





the two long egg sacs are present which are so characteristic 

 of the Copepoda (Fig. 147). In some cases the minute male is 

 practically a parasite on the body of the parasitic female. The 



FlG. 146 Cyclops sp. Dorsal aspect of female ; enlarged, i.antennule; 2, antenna: 3, eye; 

 4. < vary ; 5, uterus ; 6, oviduct ; 7, seminal receptacle ; 8, egg sacs ; 9, caudal forks ; 10, anus ; 

 11, compound segment, consisting of last thoracic (with genital opening) and the first 

 abdominal. (Partly after Hartog, from Shipley and MacBride's Zoology. I 



gills of fishes form a favorite point of attachment for th 

 parasites, which sometimes attain a length of seven centimeters. 

 In one group of the Copepoda the body is greatly flattened 



