TH?: WESTERN PINE-DESTROYTNO BARKBEETLE. 21 



to iittiirk ami kill llic limlicr in ii(lj(>iiiiii>^ licultliy forests. Indeed, my ol)serviition leuds me 

 to conclude tlmt a considerate nunilxT of f:;iidied pine trees may easily form u micleus for a 

 destructive invasion hy it. 



Ill the same hiillct in, uiidci' tlic licad of " Tlic western vcIIonv |)iiu'," 

 he says : 



It has in Dendroctouus hnriroini'^ a most pernicious enemy, which |)cncl rates and exca- 

 vates windini; <jalleries tlirou<;li the livin>j l)ark of the (inest trees, thus .speedily causiti<; their 

 deatli. Very many trees have died and are dying from tiiis cause, and tlu- dead ones are 



Clint rihiit iii<; to I he spread of forest fires. 



SpcciiiKMis of tlic iii.scct !uul its work occiijiiod a proniiiicnt pliice in 

 the exhaustive e.\hil)il of insect enemies of forests tind forest j)rodiicts 

 at the Louisiana Purcliase Exposition at St. Louis, in 1904, and the 

 Lewis and Clark (Vntennitd Exjiositioii at Portland, Orej^on, in 1905, 

 and were referred to in the cataIoo;nes of the exhibits by the Bureau 

 of Entoinoloojy." 



OBSERVATIONS BY HOPKINS, 1899-1904. 



The followino; siininiarv rclatin<i: to tliis species, prepared by Doctor 

 IIoj)kins from his field notes, includes many facts wliicli liave not ])een 

 j)ublished and which have a direct bearing on the life history and 

 habits of the species in different sections of the country where it is 

 found : 



McCloud, Cai, April Jl, 1S99.— Work and dead adults were dis- 

 covered in a su*j:ar, |)ine log, evidently from a tree which was dying 

 when felled : tilso dead parent adults in ])riniary galleries, and larvtv and 

 pupte abundant in outer btirk of large dying western yellow pine with 

 the characteristic appeartince of eastern pines when d^^ing from the 

 jittack of the destructive |)ine btirkbeetle, D. frontdlis. A few immti- 

 ture adults were found in the outer bark, and evidence tlitit some had 

 emerged. This evidence wtis in the form of ai)parent exit holes in the 

 bark, which may have been ventihiting holes from main galleries, for 

 with our present knowledge it is not likely that any jidiilts could luive 

 emerged so early. 



(liitnts Pas'fi, ()r<'<j()n, IS!)!). On April 24 mnncrous dying western 

 yellow |)ine trees were found here sciitlercd through the fon>st where 

 a severe windstorm had blown down much large timber on Septem- 

 ber 24, 1S9.5. ^Oung Jidults. hirvte, jind pup;e were fotmd in the outer 

 bark of the standing trees which luid evidently been jittacked and Imd 

 coMimenced to die the previous fall. .V|)ril 2."), mnncrous trc(>s were 

 observed which died the fall before and others which were iu)t yet 

 dead. One group of .?() young trees about 2 miles north of town were 

 dying jit the toj), the leaves turning yellow and brown. .Ml trees, 

 without exception, were either infested or had b(>en infested with I), 

 hrericomi.s-, and every indication |)ointed to this species as primarily t«» 



a Buls. 48 and 53, Bur. Ent.. U. S. Dept. ARric. 



