26 



when the beetles occur in great numbers that thej^ can overcome the 

 resistance of the living' trees. 



The following is a list of the common and scientific names of the 

 woodpeckers of northern New England, kindly prepared for me by 

 Dr. C. Hart Merriam, Chief of the Biological Survey, U. S. Depart- 

 ment of Agriculture: 



Hairy woodpecker. _ . . . D.-yobates irUlosus. 



Downy woodpecker _ _ . . Di-yohates piibescena medianua. 



Arctic three-toed woodpecker , . Picoides arcticus. 



Banded three-toed woodpecker . Picoides americanux. 



Yellow-bellied woodpecker Sjihyrapieus variua. 



Red-headed woodpecker . . Melanerpes erythrocephalns. 



Flicker. . . . _ _ Colaptes auratus luteus. 



Plicated woodpecker CeopTdoeiis pileatus abietorum. 



No positive evidence was obtained as to which one or more of these 

 birds is to be credited with the larger part of the beneficial work, 

 but, from such observations as were made in the woods and informa- 

 tion given by Dr. Merriam, and through one of his correspondents, 

 Mr. William Brewster, at Bethel, Me., it would appear that the Arctic 

 thi^ee-toed and banded three-toed woodpeckers render by far the 

 greatest service, and probably do their principal feeding during the 

 winter on the species of insect now under consideration. 



A FUNGOUS DISEASE OF THE BEETLE. 



While quite a number of beetles and larvte were found which had 

 evidcutly perished from a fungous disease, the percentage dyiug from 

 this cause was not sufficient to be of any perceptible benefit. 



CLIMATIC CONDITIONS. 



While very severe freezing, or a sudden change from cold to warm, 

 or vice versa, may kill a great many of the pupse, young beetles, and 

 even the larvfe, except in a few cases but little evidence was found 

 showing that these conditions had produced appreciable effects. 



THE PRINCIPAL INSECT ALLIES OF THE SPRUCE-DESTROYING 



BEETLE. 



Among the large nuuiber of different kinds of insects which come 

 to the aid of the spruce-destroying beetle, or follow its attacks, 

 there are at least two which are worthy of especial mention in this 

 connection; one is the spruce Polygraphus,' or lesser spruce bark 

 beetle, while the other is the spruce Tetropium.^ 



THE SPRUCE POLYGRAPHUS. 



This is by far the commonest secondary enemy of the spruce 

 throughout the spruce region of West Virginia, and was found to be 

 exceedingly common in all of the sections visited in northwestern 



' Polygraphufi rufipennis Kirby. ^ Tetropium cinnamoptenim Kirby. 



