82 



BULLETIN 67, UNITED STATES NATIONAL MUSEUM. 



Fig. 126.— A Buprestid beetle 

 Agrilus srNUATUs: a. Larva 

 6, beetle; c, pupa. 



of the tree is more profitable than the side exposed to the sun. The 

 numerous Buprestidse, Elateridss, Ptinidse, Cerambycidse, Melan- 

 dryidae, etc., which breed in the wood can be obtained only with 

 difficulty. Some specimens may be cut out from their holes by a 

 skillful use of the knife or hatchet; others (especially the Bupres- 

 tidse) may be found resting on or crawling over the trunk in the 

 bright sunshine, while the more nocturnal species may be found on 



the tree toward evening or after dark, when, 

 of course, a lantern must be used. A large 

 proportion of the species living in the trunks 

 of dead trees also breeds in the dead branches 

 of otherwise healthy trees, from which they 

 can be beaten into the umbrella, or where the 

 use of the knife is more practicable than in 

 the large trunks. The trunks of freshly felled 

 trees attract numbers of Cerambycidse and 

 Buprestidse and have to be carefully looked 

 over, while the drying foliage of such trees 

 affords an excellent opportunity for the use 

 of the umbrella. 



Beating living trees, shrubs, and vines. — The success of beating into 

 the umbrella branches of living trees and shrubs depends on the 

 particular kind of tree or shrub, on the condition and situation of 

 these, and largely also upon the season. Pine trees are very pro- 

 ductive from early in the spring to early in the summer, but much 

 less so in midsummer and later on. Young oak trees or oak shrubs 

 are much more preferred by the leaf-eating Coleoptera 

 peculiar to this tree than the older trees. The beech, 

 which, next to the oak, is the best tree for wood- 

 boring species, harbors but few leaf-eating species. 

 The leaves of the chestnut are also generally not attacked 

 by Coleoptera; still a surprising number of species can 

 be beaten from this tree when it is in blossom. There 

 is not a single species of Coleoptera known to live in 

 the wood or to feed on the leaves of the holly (Ilex 

 glabra); still it will pay the coleopterist to beat this 

 tree when it is in bloom. Trees, shrubs, and vines in 

 the interior of unbroken forest districts are, as a rule, 

 unproductive, while the edges of the woods, narrow strips of hedges, 

 and especially solitary trees, are excellent collecting places. In the 

 Rocky Mountains, especially in the more southern sections, long 

 stretches of mountain slopes are occasionally perfectly bare of vege- 

 tation with the exception of a few solitary, sickly looking, and 

 dwarfed trees, but every one of these is a veritable gold mine to 

 the coleopterist with his umbrella. 



Fig.127.— A Cara- 



BID OR GROUND- 

 BEETLE, COVIN A 

 IMPRESSIFRONS. 



