104 FIFTH ANNUAL KEPORT 



in the Prairie Farmed' of February 2d, 1867. I first became acquainted 

 with the injurious nature of this beetle, through Mr. Arthur Bryant, 

 of Princeton, Illinois, and the case of Mr. Bliss is the first on record 

 of its doing damage in Missouri. The following passages from a letter 

 received in 1867, from Mr. Bryant, convey an idea of the loss the 

 insect has occasioned him, and contain some facts regarding its mode 

 of working : 



I send you, by express, some pieces of wood and bark containing 

 a worm which has for some years been destroying the hickory-trees 

 on my farm. The trees grow on a strip of rich soil, striking the prairie 

 on the east side of the forest, bordering the Bureau River. When I 

 settled here, thirty-three years since, this tract was covered with 

 bushes, with a few scattered trees, and was annually ravaged by fire. 

 Since then a tall, dense growth of thrifty young timber, mostly bitter- 

 nut hickory, {Carya amara)^ has grown up. The insect commenced 

 its ravages about ten years since, and has killed many hundreds of 

 fine young trees. It has sadly thinned my beautiful grove, and bids 

 fair to destroy all the hickory trees in it. It is found in other locali- 

 ties in this vicinity. 



I first detected the insect in its winged form in September, 

 1855. Noticing some small holes, newl}' bored, in the smooth bark of 

 a hickory-tree, I found, on examination, in each hole a small black 

 beetle, which subsequent investigation satisfied me was the parent of 

 the mischief. The mode of operation appears to be as follows : Boring 

 through the bark, the insect forms a vertical chamber next to the 

 wood, from half an inch to an inch in length, on each side of which it 

 deposits its eggs, varying in number from twenty to forty or fifty in 

 all. The larvas, when hatched, feed on the inner bark, each one follow- 

 ing a separate track, which is marked distinctly on the wood. Some 

 trees contain them in such numbers that the bark is almost entirely 

 separated from the wood. In many cases the upper part of the tree 

 is killed a year or two before the lower part is attacked. 



The insect has continued its ravages, and doubtless will do so 

 until Mr. Bryant's entire grove is destroyed. 



Through the kindness of Mr. Bryant I have, since 1867, been able 

 to fully study the habits of the species. 



There is, in Europe, a very closely allied beetle (^Soolyius destriio- 

 tor) known to attack the Elm. It was for a long time a contested 

 question as to whether this insect ever attacked healthy trees, and 

 there were not wanting men of repute who considered it the effect 

 rather than the cause of disease.* But Mr. Spence long ago discov- 

 ered that though the female is probably seldom guilty of depositing 

 her eggs in healthy, vigorous trees, both she and the male bore into 

 such trees for food, thereby causing an unhealthy state of the tree, 

 by which it is rendered an agreeable nidus for the insect. The habits 

 of our Hickory Scolytus are similar to those of the Elm; but while, 

 according to the best authority, the vertical channels formed by the 



I* See Westwood, in Gardeners' Magazine, (Eug.) , Vol. XIV, p. 303. 



