39Q 



REPORT OF THE COMMISSIONERS OF 



ovipositor about three inches long, whence its common name of "long sting." This 

 beneficial parasite may frequently be seen with its long ovipositor arched over its 

 back, and the membranes of its abdomen much distended as it forces its slender tool 

 deep into the wood in an effort to place its eggs in the vicinity of a borer. The male 

 is a smaller insect. On splitting open a log containing Tremex larvae, the white, 

 legless maggots of this parasite may be found sucking the life fluids from the borers. 

 Like the Tremex, the females of the long sting emerge from the trunk of the tree 



Figure 10. — Pigeon Tremex: a, larva showing the Thalessa larva fastened to its side; d, head of larva; c, pupa 

 of female; d, male pupa; e, adult female — all slightly enlarged. (After Marx.) 



(Insect Life, VoL I., Fig. 39, C. S. Dept. Agriculture.) 



through holes about the size of a common lead pencil. The various stages of this 

 interesting parasite are well represented in the accompanying figure (i i). 



Remedies. Badly infested trees should be cut and burned before the following 

 June in order to prevent the maturing of the insects they contain. If the trunks of 

 shade trees were treated early in July with the carbolic acid wash described on a 

 preceding page, it is probable that deposition of eggs would be prevented to a con- 

 siderable extent. Indications of oviposition should be looked for in the fall most 

 carefully and the young borers should be dug out and destroyed. Wherever signs 

 of recent boring occur, an attempt should be made to find the offender. The digging 

 out will rarely do more injury than the borer would otherwise cause. If there is 

 reason to believe a burrow inhabited but no larva can be found, the use of carbon 



