Nov., '06] ENTOMOLOGICAL NEWS. 317 



on the tree, but out of doors and exposed to the winds all 

 infested leaves fall. A storm on May 28th, 1906, caused a great 

 many leaves to fall from the maple trees, and most of them 

 were cut nearly off by this stem borer. 



Either before or after the petioles fall to the ground, the 

 larvae eat their way out, leaving small circular holes in the 

 stems, usually near the middle. These holes may be seen in 

 che accompanying illustrations. 



LIFE HISTORY OF THE INSECT. 



The eggs are laid by the females about the first week in May, 

 but it is believed that oviposition may be kept up for some 

 time. The eggs soon hatch, but it is not known how long a 

 time is required. The larvae tunnel in the stems for about one 

 month, causing the leaf blades to fall in about three weeks and 

 the stems to drop from ten days to two weeks later. On or 



v 



before the dropping of the stems the larvae go into the ground 

 and make cells in which they pass the pupa stage. Our cages 

 were three inches deep, and the pupa cases were found at the 

 bottom. It is not known whether the pupa stage is assumed 

 at once or not until the following spring. Adults emerge 

 about May ist, and soon begin to lay eggs. 



The difficulty encountered in rearing the adults of this 

 species, and their great mortality in the breeding cages, show 

 the insect to be extremely delicate after passing the larval 

 stage. 



WHERE THE EGGS ARE LAID. 



The eggs are laid at the distal end of the stem or base of 

 the blade, at the point where the chief veins branch from the 

 stem. The process of egg laying has been observed, and the 

 scars may be found on many of the leaves. It seems strange 

 that the egg should be deposited in a portion of the host plant, 

 which is later severed from the burrow containing the larva. 

 Nineteen eggs were found in the abdomen of the female ex- 

 amined. 



FOOD PLANTS. 



The insect has been observed as attacking the leaf stems of 

 tlic sugar, Norway and sycamore mnplrs. From time to time 



