284 Recent Literature. [April 



G Red-breasted Nuthatch Siiia canadensis 



G B Chickadee Pe?itheslcs atricavillux 



G B Veery Hylocichla fuscescens 



G B Wood Thrush Hylocichla musteline, 



G B Robin Planeslicus migratorius 



G Bluebird Sialia siali-s 



Messrs. Rogers and Burgess, authors of the report on the gipsy and 

 brown-tail moths, note that "A few species, among which may be men- 

 tioned the Crow, while destroying many of the larva?, undoubtedly aid 

 the spread of the gipsy moth by dropping live caterpillars in uninfested 

 sections." The subject of the distribution of the moth by birds has no- 

 where received as full consideration as in the original report referred to 

 above (pp. 235-240). It is recorded there that the Wood Thrush, Chicka- 

 dee, and Least Flycatcher were seen to drop caterpillars or female gipsy 

 moths from their beaks, and that a young Baltimore Oriole refused a 

 larva which the parent bird brought, dropping it over the side of the nest. 

 Circumstantial evidence points to the formation of new colonies about 

 Crow's nests. 



The authors, Messrs. Forbush and Fernald, remark that "A bird may 

 overlook a few caterpillars near its nest, preferring to go where caterpillars 

 are plentiful rather than to search for them where they are scarce. It is 

 probable, then, that the bird which is most useful in destroying cater- 

 pillars and which feeds the largest number to its young will be the most 

 likely to aid in the distribution of the moth. The danger of distribution 

 would probably be greater in the case of the larger species of birds, were 

 it not that a caterpillar seized in the bill of a Crow would be more likely 

 to be seriously injured than one taken in the bill of a small bird. The 

 danger of distribution to distances of much more than half a mile by birds 

 in this way does not seem to be great. . . The distribution of caterpillars 

 by birds goes to prove the rule that nature does not usually work for the 

 extermination of species. While the birds are very useful as assistants 

 in the work of extermination by destroying the gypsy moths, they hinder 

 the work to some extent by distributing the larva? and the female moths. 



"No appreciable distribution of caterpillars by birds will occur, however, 

 except when caterpillars are present in large numbers, for then only will 

 birds go to a distance to secure caterpillars as food for their young. Proba- 

 bly no other form of dissemination of caterpillars by birds will materially 

 extend the moth's distribution even under the most favorable conditions. 

 Whenever the caterpillars are present in large numbers in a settled country, 

 they will be carried much farther and scattered abroad more widely by 

 man and domestic animals than by birds. In woodlands remote from 

 civilization, birds may be the principal factor in diffusing the moth to a 

 short distance from badly infested spots, but the distribution of the moth 

 in such places is not of so much moment as in cultivated and settled regions. 

 If the moth were allowed to increase and spread over the whole State, we 



