THE CANADIAN ENTOMOLOGIST. 149 



far as my experiments went they showed the London Purple to be a suc- 

 cessful remedy and as applicable to these worms as to any of the Saw-Fly 

 group. No adults were observed, and none of the larvae I had under my 

 observation matured ; so the matter necessarily came to a rest. 



During the summer of 1883 the worms appeared in much greater num- 

 bers and distributed over many more trees. At the same time and upon 

 the same trees with these worms I observed adult Saw-Flies that I could 

 have little doubt were the mature worms, although I did not succeed in 

 finding the eggs and obtaining the larva; from them, nor have I reared 

 them as yet from the immature stage. Their presence in large numbers 

 at the time when newly hatched larvcc were appearing plentifully day after 

 day, and the fact that the adult must be an insect of this particular kind, 

 left little doubt as to their connection. During the present season I have 

 observed these adults as early as April 15th. and the larvae but little later, 

 while the eggs from which the larvje hatch were found deposited in the 

 petiole of the leaf. 



The adults are the Selandria bar da of Say,* the food plant of which, 

 so far as I can find, has never been recorded. 



No account of the larva or of its work is given in any of the works 

 that I have been able to consult, and as it seems to me of too much 

 importance to remain unnoticed, I venture to give what I know of its 

 history with the practical results of my study, notwithstanding the doubt 

 that rests over some parts of its life histor) . The pressure of other duties 

 at the time these worms were at work prevented me from giving them the 

 time they certainly deserved. 



LIKE HISTOKY. 



The eggs are deposited in rows along the sides of the petiole just 

 beneath the outer bark, and so neatly that it is almost impossible to detect 

 any break in the epidermis. Usually there are from six to ten on a leaf. 

 They evidently increase much in size before hatching, pushing the bark 

 up in a blister-like elevation, and if cut out of their covering are found to 

 be very soft, the outer membrane exceedingly delicate and easily ruptured. 



* In order to be certain that my determination of the species was correct, I sent 

 specimens to Mr. E. T. Cresson, of Philadelphia, and he has kindly compared them 

 with the specimens in the collection of the Am. Ent, Soc, and pronounces them identi 

 cal, except a slight difference in size, 



