120 



USEFUL BIRDS. 



moth (as cited on p. 17), may be mentioned here in refu- 

 tation of the assertions of European writers to the effect 

 that hairy caterpillars are not eaten by birds. The fact that 

 birds have been seen to feed more commonly on such cater- 

 pillars in Massachusetts than elsewhere suggests the proba- 

 bility that this habit of feeding is local and exceptional. 

 But records of the destruction of the forest tent caterpillar 

 by birds in New York and New England, as given by Miss 

 Soule, Dr. Felt, and others, show that the species that attack 

 hairy larvae in Massachusetts are useful in this respect else- 

 where. There are many other records in the literature of 

 American economic entomology and ornithology which might 

 be offered to corroborate the specific instances hereinafter 

 given. This habit of birds has been observed more in Mas- 

 sachusetts than elsewhere merely because the conditions here 

 have been exceptional, and the birds have been carefully 

 watched. 



It seems quite probable, from my experience, that those 

 extremely hairy and destructive caterpillars, the Arctians, 



commonly represented by the yellow 

 bear (Diacrisia virginica) and the 

 woolly bear (Isia isabella)^ are not 

 chosen as food by many birds. Still, 

 I have never known either of these 

 species to be very abundant, and 

 think it not improbable that their comparative scarcity may 

 be largely due to their being eaten when very small by birds. 

 The earlier Thrushes 

 take some of these 

 larvae that winter 

 upon the ground. 

 Should these cater- 

 pillars ever become 

 very abundant at any 

 time, it seems probable that other birds would attack them. 

 The tussock moth caterpillars (Hemerocampa leucostigma) 

 and others, which Dr. Packard instances as probably immune 

 from the attacks of birds, are eaten by a goodly number ; 

 and I have no doubt that the exemption of our trees in the 



Fig. 38. The woolly bear 

 caterpillar. 



Fig. 39. The yellow bear caterpillar. This and 

 the woolly bear are destructive hairy species, such 

 as are eaten by Thrushes, Robins, and Bluebirds. 



