82 



BOARD OF AGRICULTURE. [Pub. Doc. 



its way to our shores ; yet so comparatively harmless was it 

 in its native environment that we have but just learned au- 

 thoritatively that it hails from northern China. Beyond 

 doubt its increase at home is restricted by certain parasites, 

 and when it was imported to the United States the importa- 

 tion did not include the beneficial agents. 



Of these imported pests, the one at present of the greatest 

 general importance in Massachusetts " is the European elm- 

 leaf beetle (GaleruceUa luteola, Muell.). This insect has 



FIG. 1. Different stages of the elm-leaf beetle: a, eggs; 6, larvae; c, adult; e, eggs 

 enlarged; /, sculpture of eggs; g, larva enlarged; ft, side view of greatly enlarged seg- 

 ment of larva; i, dorsal view of same; j, pupa enlarged; k, beetle enlarged; I, portion 

 of wing-cover of beetle greatly enlarged. From Riley, Report United States Depart- 

 ment of Agriculture, 1883. 



now established itself in nearly all our cities and larger 

 towns. It has been characteristic of the northward spread 

 of the beetle that its routes of march have been particularly 

 along water courses and the seaboard. One reason for this 

 readily suggests itself. These well-watered localities are the 

 ones in which the elm most freely develops. It divides 



