THE GENUS DENDROCTONTJS. 163 



or, in other words, the stumps of trees felled in the fall and winter 

 should not be barked to destroy the broods of this beetle before June 

 or July, but the barking must be completed before the following 

 March. Trees felled during the spring and summer to serve as traps 

 should not have the bark removed for at least two months after the 

 trees are felled. 



In some sections of the countr} T this beetle appears to be attracted 

 to the trunks of felled trees much more than to those of others, 

 depending probably more on the species of tree and local conditions 

 relating especially to the presence or absence of certain other insects 

 which would or would not interfere with the development of their 

 broods. 



In the vicinity of Monterey, Cal., it was found by the writer abun- 

 dant in September in the bark of trees felled by storm the previous 

 April. This suggested the utilizing of trap trees in such localities 

 to attract the beetles to the bark of the trunks, as well as to that on 

 the stumps. 



BASIS OF INFORMATION. 



The above statements are based on investigations by the writer 

 in many localities in different sections of West Virginia in 1890 to 

 1894; at McCloud and Berkele} r , Cal., Grants Pass and Albany, 

 Oreg., near Spokane, Wash., and at Moscow, Idaho, April to June, 

 1899; in the Black Hills, South Dakota, 1901 and 1902; at Priest 

 Lake, Idaho, August, 1902; at Del Monte and Monterey, Cal., Sep- 

 tember, 1902; at Williams, Ariz., September, 1902; at Vermejo, 

 N. Mex., May, 1903; at Flagstaff, Ariz., May, 1904; in the Yosemite 

 National Park, California, June, 1904; at Brunswick and Portland, 

 Me., May and June, 1900; at Maiden, Wyoming [Melrose], and Lynn 

 Woods, Mass., May, 1906 (in Norway spruce defoliated by gipsy 

 moth); at Milford, Pa. ; May, 1905; at Pink Beds, N. C, July, 1904; 

 at Manitou Park and Palmer Lake, Colo., October, 1905; in Ventura 

 County, Cal., June, 1904; at Garland, Colo., June, 1906; on Grand 

 Island, Michigan, July, 1907; by Mr. W. F. Fiske, at Webster, N. H., 

 June, 1904; at Pink Beds, N. C, May, 1905; on Grand Island, Michi- 

 gan, October, 1906; at Capitan and Cloudcroft, N. Mex., March to 

 May, 1907; by Mr. J. L. Webb, in the Black Hills, South Dakota, 

 June to October, 1902; at Flagstaff, Ariz., June to August, 1904; in 

 the vicinity of Centerville, Idaho, May to August, 1905; in the Cap- 

 itan Mountains, Lincoln National Forest, and White Mountains, New 

 Mexico, and in the Chiricahua National Forest, Arizona, June to 

 September, 1907; by Mr. H. E. Burke, at Palo Alto, Cal., May, 1905, 

 May, 1906, and September, 1906; in the Yosemite National Park and 

 vicinity, at Wawona, Summerdale, Little Yosemite, and Yosemite, 

 Cal., May to September, 1906; at Kamas, Panguitch, and Panguitch 



