DIVISION or 



FORESTRY 



COLLEGE Of A AGKtCU 

 UNIVCKSITY Of CALIFORNIA 



THE SPINY ELM CATERPILLAR 



BY CLARENCE M. WEED 



In New Hampshire during the last three years there have 

 been frequent complaints of injury to the foliage of elm trees 

 by a black, spiny caterpillar. The extent of the injury ap- 

 pears to have been increasing from year to year until, in 1899, 

 it attracted very general attention. In some localities the 

 damage done was compared to that done by the hosts of the 

 Forest Tent Caterpillar or Maple Worm. The correspond- 

 ence of this station, as well as trips in the field, has shown 

 the desirability of a full statement of the life history of the 

 insect, and of the remedial measures to be taken against it. 



Fig. 41. Mourning Cloak or Antiopa Butterfly. 



This bulletin, therefore, is issued: it embodies a statement of 

 the results of the studies of the insect carried on at this sta- 

 tion by the entomologist and his assistant, Mr. W. F. Fiske, 

 as well as a summary of the previous knowledge of the species. 

 It aims, in short, to place before the people of the state a brief 

 account of all that is known of the pest in so far as it may be 

 of practical value. 



