Twelfth Eeport of the State Entomologist 297 



able place on which to settle. This is especially true of the males, as their 

 snow-white cocoons are more rarely found in the center of a mass of 

 the females than at the ends of dry twigs and other places unsuitable for 

 the opposite sex. An abundant secretion of honey-dew occurs from the 

 time the insects resume their activity in the spring until near the time 

 that the young appear. The males remain in the pupa state for a few 

 days only. A few pseudimagos emerge first (about six days after pupa- 

 tion), which are followed a week later by the perfect males. These soon 

 perish after pairing, — the young not appearing until over two months 

 later as indicated above. Soon after pairing, there is a marked difference 

 in the features of the female. Her form changes from elliptical to oval, 

 the secretion of the wax is more copious and is mainly from the lateral 

 spines instead of from both lateral and dorsal as during the early autumn. 



Means of Distribution. 

 The comparatively recent introduction of this pest and the establish- 

 ment of its colonies in distant states, show very clearly how great a factor 

 the shipment of nursery stock maybe in the distribution of injurious 

 insects. The rapid spread of this insect in eastern cities where it has 

 obtained a foothold is surprising, and must be largely attributed to other 

 means. It was not discovered in Albany until i88g. In the short space 

 of seven or eight years it has spread to a large number of trees in all 

 parts of this city and of Troy, where it is so generally distributed that 

 perhaps three-fourths or even a greater portion of the elms are infested to 

 some extent by it. It is by no means easy to explain how this spread was 

 effected unless through the agency of birds. That notorious public pest, 

 the English sparrow, has undoubtedly been an important agent in its distri- 

 bution. It is but the work of a moment for the active young to crawl upon 

 the foot of a bird touching the limb, and leave it at any later time. 

 Many infested trees are so isolated, that there must be some such means 

 for the conveyance of the wingless forms from one tree to another. It 

 is possible that some of the immature insects falling with the leaves in the 

 autumn may survive the winter and found colonies in new localities to 

 which the leaves are carried by the winds ; but this means of distri- 

 bution would at best be quite limited and uncertain, and by no means 

 could account for the spread of the wingless female throughout so 

 many states in less than a score of years. 



