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unable to fly very far or high, deposits ber eggs in the first snitable 

 place that ofters. I have but little doubt that the larva, when getting 

 too large for the branch in which it is feeding, migrates to a larger 

 branch, as affording sufficient room for its development, for in my insect 

 room, where the specimens are kept for breeding, they often do migrate 

 from a small branch and eat their way into a larger one, and they liave 

 even eaten into the yellow pine flooring and covered themselves with 

 their frass ; one migrated nearly 30 feet and went into the white pine 

 window-casing, where it remained until it pupated, and emerged as a 

 moth. Experience has shown in a great many cases that they are 

 amply able to take care of themselves, and when in their burrow and 

 drawn up the thoracic and anal shields form perfect opercula imper- 

 vious to all external enemies. 



The family of Zeuzeridiie are very remarkable from the fact that the 

 females have a long and quite hard ovipositor, by means of which they, 

 probably, are able to introduce their eggs into the soft tissue between 

 the bud and the node on which it is situated so that the young larvae 

 when hatched can without much difficulty enter the twig to feed upon its 

 interior. In Europe it is recorded as feeding ujion six species of trees, 

 and an English writer has made the statement that fruit trees pierced 

 by this insect bear even more abundantly than do those untouched by 

 it. However this may be, most of the limbs affected break oft" entirely 

 with us, provided the larva attains its full growth, for it then, in many 

 cases girdles the limb, when a storm is most sure to break it off. After 

 every storm great quantities of limbs can be seen either entirely broken 

 oft' or still hanging on the trees. In 1893 we spent two months in fight- 

 ing this insect alone in our city parks, collecting wagon loads of limbs 

 and branches, and destroying the larva? or pupa?, as the case might be. 



This is one of the most difficult insects we have to keep in check, 

 for it works in secret and does not disclose its whereabouts until the 

 damage is done, disfiguring and destroying many of our most valuable 

 shade and ornamental trees, and particularly our beautiful American 

 white elm, which, if not killed outright, is thrown out of character by 

 severing its leading branches. In many cases the entire head of the 

 tree is severed from the trunk, and it may have attained a diameter of 

 six or more inches. 



Again we find as many as six larvse in a single tree but three inches 

 in diameter, anj^ one of which is able to destroy the tree if not removed. 

 These are cut out as soon as detected, and all the young elms 

 undergo a rigid examination three or four times a year. A system of 

 lights has been projected for use in the Central Park, but as yet the 

 means to the end desired has not been given. The light would attract 

 many males of this species and some females, but most of the females 

 are too heavy to fly far, or at least seem to be unable to when in cap- 

 tivity, but the lights would attract other noxious moths which could be 

 easily taken in traps. This insect, working in secret, can only be 



