71 



The distribution accorded this species by Dr. Horn comprises the 

 United States from Maine to Texas and westward to the Rocky Moun- 

 tains. 



PARASITIC ENEMIES. 



This borer undoubtedly has many insect enemies, as several genera of 

 parasitic Hymenoptera are known to attack species of the same genus. 

 Of the parasitic species observed in this vicinity, Spathius simiUimus 

 Ashm. was the most abundant, and is an undoubted parasite of Agrilus 

 bili neat us, as the circumstances of its capture in the galleries of this 

 buprestid indicate. It was exceedingly 

 abundant at Wedderburn in 1893, and prob- 

 ably played an important role in reducing 

 the numbers of its host. One other parasite 

 has been reared with this species, but it has 

 not been identified at the present writing. 



OTHER INSECTS ON CHESTNUT. 



A considerable number of other insects 

 were observed on the infested chestnuts, 

 principally wood-boring Coleoptera. Many 

 of these are well-known enemies of this tree, 

 but the list includes also a number new to 

 the chestnut. Space will not permit of the 

 mention of more than a few of the more 

 important or interesting species at this time. 

 With scarce an exception they were only 

 secondary in their attacks and it is hardly likely that more than a very 

 small proportion are capable of initial injury to trees. The list follows : 



F rogr aphis fasciatus DeG. — This cerambycid was the most abundant 

 borer in chestnut. It occurred in all stages under bark of recently 

 dead trees, June to 8. No imagos had issued at that time. Also 

 reared from oak and maple. 



Leptura zebra Ol. — Recorded from oak. Found in different seasons 

 and localities in abundance on the foliage of chestnut. 



CJtrysobotliris 6-signata Say. — Found with Chrysobothris femorata on 

 the trunks of recently felled trees, beared by the writer from beech : 

 also affects the birch. 



Alaus oculatus Linn. — Larvae of this species were noticed under bark 

 at the base of trees. 



Dendroides canadensis Latr. — Occurred in all stages and in Borne 

 abundance under the bark. 



Oryptorhynchus bisignatus Say. — Taken on trunk. Previously noticed 

 by the writer on chestnut and beech; probably lives in bark. 



Cryptorhynchus obtentus libst. — Isolated examples of the adults. 



Fig. 42 — Agrilus bilineatus: a, adult 

 beetle; b, antenna of same-. £ .claws 

 of posterior tarsi of female; a,, 

 sameof male; c, larva — a, andc, en- 

 larged; b, J , and $ , more enlarged 

 (original). 



