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UNIVERSITY OF WISCONSIN STUDIES 



exceptions in one class to the last statement: Gephyrocharax 

 valenciae, Symbranchus marmoratus, and Aquidens pulcher 

 all have a large number of parasites per individual and are 

 infected with a large number of species of parasites, but few 

 individual fishes are infected. 



All things considered the fishes showing the highest parasitic 

 infection rank in the following order: (1) Aquidens pulcher; 

 (2) Astyanax bimaculatus and Crencichla geayi; (4) Symbranchus 

 marmoratus, Curimatus argenteus, Hoplias malabaricus, Gephy- 

 rocharax valenciae. It will be noted that those toward the 

 end of the list generally have the diet restricted to fewer items 

 (Table V) than those at the beginning. This, with the results 

 presented in the last paragraph, may indicate that a restricted 

 diet is associated with a smaller percentage of infected fishes. In 

 other words, the fewer kinds of food a fish eats, the less likely it 

 is to be infected with parasites. 



TABLE VII 



Parasitic infection of fishes of Lake Valencia. The figures refer to number 

 of fishes infected and where there are two, the second is per cent. 



fish. 



* Numbers in this column mean number of species of parasites occurring irt each species of 



