The Horn-Tails 



Fig. 41. — Tremex columba. (From Insect Life.) 



It was a common sight to see females which, after laying, had 

 been unable to withdraw the ovipositor, so that they had been 



held to the trunk until they died. 

 The eggs are oblong-oval and 

 pointed at each end. 



The common parasites of the 

 lame of these horn-tails are the 

 very large and extremely long- 

 tailed Ichneumon flies known as 

 Thalessa lunator and Thalessa 

 atrata. These Ichneumon flies 

 lay their eggs in the burrows of 

 the Tremex, and their larvae feed 

 upon Tremex larvae. 



The exact facts concerning 

 the life of the Tremex larvae in 

 trunk of the tree have not been 

 studied, and the species is such 

 a common one that it will be 

 70 



Fig. 42. — Cephus pygmaeus. 

 (After Curtis.) 



