28 NEW YORK STATE MUSEUM 



list" of 46 species known to feed on the yips\- moth, Porthetria cl i s- 

 p a r Linn. He lias found 25 feeding; on the imported brown tail moth 

 caterpillar, E u p r o c t i s c h r \- s o r r h o e a Linn., 25 feeding on the forest 

 tent caterpillar, Malacosoma disstria Hiiljn., 32 feeding on the 

 apple tent caterpillar, Malacosoma amcricana Fabr., and 51 feeding 

 on cankerworms. Dr A. D. Hopkins in a recent bulletin' states that wood- 

 peckers "are the most important enemies of spruce bark beetles, and appear 

 to be of inestimable value to the spruce timber interests of the Northeast." 

 Of many hundreds of infested trees e.xamined by him, he is confident that at 

 least one half of the beetles and their young had been destroyed by the 

 birds, and in many cases it was evident that even a greater proportion had 

 perished from this cause alone. He adds that estimating 100 beetles to the 

 square foot of bark, and an average of 60 square feet of infested bark, it is 

 possible for each tree to yield an average of 6000 intlividuals ; 100 trees, 

 600,000, and so on. It is therefore plain, that if one half or two thirds are 

 destroyed by the birds and other enemies, the amount of timber the remain- 

 der kills will be much lessened ; specially is this true because the beetles 

 must be present in great numbers before they can overcome the natural 

 resistance of the living trees to injury. 



He also gives a list of the common and scientific names of the wood- 

 peckers of northern New England, prepared for him by Dr C. Hart Mer- 

 riam, chief of the Biological Survey, United States Department of Agricul- 

 ture. It is to these birds that Dr Hopkins refers, though no evidence was 

 obtained at that time as to which species was to be credited with the largei 

 part of the beneficial work. The list follows : 



Hairy woodpecker - - Dryobates villosus 



Downy woodpecker - - Dryobates pubescens medianu? 



Arctic three-toed woodpecker Picoides arcticus 



Banded three-toed woodpecker Picoides americanus 



Yellow-bellied woodpecker - Sphyrapicus varius 



' 1900 Mass Crop Rep't. July p. 34. 



=1901 U. S. Dep't Agric, Div. Ent. Bui. 28, n. s. p. 25-26. 



