34 



ings between the sexes is very noticeable. The fact that the male moths 

 &y actively, while the females do not, is also of interest, and has an 

 economic importance as well, because to a great extent this restricts 

 the spreading of the insect. 



Di$lribNtio)i. 

 We have spoken of the natural spreading of the pest, but the artificial 

 distribution by the insects falling on teams and other vehicles is much 

 more important. Teams passing under infested trees early in the spring, 

 or even when the caterpillars are half grown or more, take on a number 

 of these accidental insect passengers and transport them from i)lace to 

 place. In this way the moth has become thoroughly distributed along 

 the main lines of travel. Wood roads and other places much frequented 



by the i)ublic are also generally in- 

 fested. The grounds around Bunker 

 Hill Monument and at Mount Auburn 

 Cemeterj' are two localities which 

 remain infested from year to jear, 

 and which well illustrate the point. 

 However severe the suffering and 

 loss which have occurred in recent 

 years in the metropolitan district, it 

 is not to be compared in its economic 

 significance with that which will re- 

 sult through the spreading of the 

 moth into non-infested areas. Large 

 colonies such as now exist in Arling- 

 ton, IVledford or Maiden continually 

 menace not only the territory im- 

 mediately contiguous but also the 

 towns and cities lying along the 

 lines of travel which pass through 

 these regions. The writer has re- 

 peatedly found the caterpillars on his 

 team after a day spent in the moth 

 colonies. Several people have reported finding the gypsy moth cater- 

 pillars in electric cars. At the Oak Grove station on the Boston & Maine 

 Railroad the caterpillars literally have hung in festoons, under which it 

 was practically impossible for passengers to walk without picking up one 

 or more caterpillars. Dr. L. C. Jones of Maiden, an observant naturalist 

 as well as a skilled physician, informs the writer that he has seen female 

 moths in considerable numbers laying their eggs on trucks and sides of 

 freight cars at the Oak Grove station. These few facts taken at random 

 from a large number of authentic instances show the means by which 

 the moth is spreading from the neglected colonies, and portend a wide 

 distribution of the insect in the course of a few years. 



Food Plants. 

 ^ The gypsy moth caterpillar is remarkably polyphagous. It feeds 

 readily upon practically all our common fruit and forest trees. The 



Fig. 3. Pupa of gypsy moth. 



