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UNIVERSITY OF WISCONSIN STUDIES 



and had the largest number of parasites per individual (Table 

 VII). The latter is probably due in part to opportunities for 

 infection through its food, but is also due to the large number 

 of cysts (Trematode No. 3) present in the fins and skins of two 

 fishes captured in the Rio Castafio, July 27. These two fishes 

 were without, any of the seven parasites found in fishes from 

 the lake and the parasites they carried were not found in any 

 other locality. 



Curimatus argenteus, Cula 



This beautiful fish was not often caught and only seven 

 specimens were examined. Four were without parasites; one 

 carried a Parspina bagre cyst on its dorsal fin; another had 

 forty trematodes in its intestine; and the other had a trematode 

 cyst (No. 2) dorsal to the swim bladder. 



Gephyrocharax valenciae, Sardina 



Table VI D summarizes the parasites found in this fish. 

 Although it is commonly eaten by other animals, it does not 

 contain an unusual number of immature parasites. 



TABLE VI. D. GEPHYROCHARAX VALENCIAE 



Hoplias malabaricus, Guabina 



This is the largest and fiercest predacious fish in Lake 

 Valencia. As one would expect it bears a very large number 

 of parasites per individual and is infected with eight different 

 species. (Table VI E). Every individual examined was infested 

 with encysted nematodes. 



