Arctiidse 



Genus ISIA Walker 



Three species belong to this genus, one found in Argentina, 

 the other in Turkestan, and the third in the United States 

 and Canada. 



Fig. 68 Isia isabella, 8 . {. 



(After Hampson.) 



(i) Isia isabella Abbot & Smith, Plate XVI, Fig. 13, $. 

 (The Isabella Tiger-moth.) 



This common insect is found everywhere in the United 

 States. The caterpillar is the familiar "woolly bear," which 

 may be often seen by the roadside rapidly making its way in the 

 fall of the year to a hiding-place in which to hibernate, or, in 

 the spring, to some spot where it may find food. It is reddish- 

 brown in color, black at either end. When disturbed, it curls 

 up and lies motionless, as if feigning death. To "caterpillar," 

 in the slang phrase of the Middle West, is to silently succumb 



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Fig. 69. Isia isabella. a. larva; b. pupa. 



and yield to the unavoidable. The larva feeds freely upon a great 

 variety of herbaceous plants. It is fond of the grasses, and 

 particularly likes the leaves of the plantain {Plantago). There 

 does not appear to be any marked tendency to variation in this 

 species. Both the moth and the larva are common objects, with 

 which every American schoolboy who has lived in the country 



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