70 NEW YORK STATE MUSEUM 



season change to pupae sometime about the middle of May or earher, 

 and the beetles begin to appear the latter part of that month and con- 

 tinue to emerge for some time, examples having been taken as late as 

 Aug 24. The eggs are deposited on the bark in June, according to the 

 observations of Dr Fitch, but it would seem very probable that oviposition 

 may occur much later, as the beetles are abroad till into August. The 

 attack usually begins at the base of the tree. The young grub works its 

 way under the bark and begins feeding on the tissues, making a serpen- 

 tine burrow. The boring increases in size with the growth of the larva and 

 in the course of time the tree may be completely girdled and then it must 

 soon die. Dr Packard, writing in 1870, calls attention to finding three sizes 

 of larvae and the writer has found it comparatively easy to separate those 

 taken from a badly infested piece of limb in a similar manner. 



Food plants. This insect appears to infest the white elm almost exclu- 

 sively, though Dr F"itch records it as breeding in the slippery elm. No 

 indications of its attacking either the English or Scotch elms have been 

 seen in Albany. There is a record of this species having been reared from 

 maple, but it would seem that the infestation must have been accidental. 



Associated insects. Two species of curculionid or snout beetles may 

 frequently be observed working in elms attacked by this pest, but they 

 appear to follow and not to initiate an attack. M a g d a 1 i s a r m i c o 1 1 i s 

 Say and M. barb i t a Say are both small beetles a little over y^ inch long, 

 the former reddish, and the other black [pi. 3, fig. 5, 6, 6^r] and are 

 treated of on pages 71-73. The cocoons of a parasite, Melanobracon 

 simplex Cress., occurred in numbers under the bark where Saperda lar- 

 vae were abundant, on which the ichneumon preys. 



Another ally of Saperda, Neoclytus erythrocephalus Fabr., 

 is less common than the two species of Magdalis. This is a small reddish 

 beetle about 3/^ inch long and prettily marked with three yellowish, nearly 

 transverse lines on each wing cover. It usually follows Saperda attack in 

 much the same way as does Magdalis. 



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



