ANIMAL PARASITES 



175 



ing of the pigeon's parasites is the one shown in 

 Fig. 115, which is supposed to confer a benefit 



I" 



Fij;. 114. I'ar.u^ite of the crow 



Lipon the bird by thinning its bodv-pluniage as 

 the weather grows hot. 



Simihir slender - bodied and possibl\' useful 

 parasites are toiincl on man\' birds, including the 

 domestic fowl, coot, water-hen, house-martin, &c., 



