DATE OF INFESTATION. 



A determination of the time when this insect was introduced into 

 Massachusetts is impossible to make with any certainty and only 

 conjectures can be offered. If it was brought in on Japanese nursery 

 stock it was undoubtedly before 1902, as official inspection of the 

 nurseries was begun in that year and none of the inspectors observed 

 these cocoons either then or during subsequent inspections till the 

 present summer. Before 1902 the Japanese nursery in this locality 

 was inspected for a year or two at the request of the owners by Mr. 

 A. H. Kirkland and if it had been present then, it would certainly 

 have been discovered. These facts taken in connection with the 

 rather large area over which the insect now occurs lead to the opinion 

 that if it was introduced on nursery stock it was probably before the 

 year 1900. 



LIFE HISTORY. 



The life history of Cnidocampa flavescens does not seem to have 

 been fully worked out in the Orient, and has thus far not been com- 

 pleted here. 



The insect passes the winter in the cocoon but does not pupate 

 until spring, retaining during the winter its larval form but losing 

 most of its color. The moths emerge from the cocoon during the 

 latter part of June and first of July and one in confinement laid about 

 fifty eggs on the side of a breeding cage but these failed to hatch and 

 were undoubtedly infertile. The length of time spent in the egg 

 therefore cannot be stated nor the time during which the larva feeds, 

 but it is probable that cocoon making occurs during the latter part of 

 September or the first of October, and it is evident that there is but 

 one brood a year. 



DESCRIPTIONS. 



Egg. The unfertilized eggs referred to above were regularly oval 

 in form, measured one and three-eighths mm. by three-fourths mm.^ 

 and were creamy white in color. The chorion showed a slight pearly 

 luster under a lens, but no markings or micropyle were perceptible 

 with this magnification. The eggs were laid side by side, touching 

 each other, on the wood of the frame of the breeding cage though 

 leaves and twigs of trees were available. 



Larva. The larva is one of the "slug caterpillars " but as it has 



