34 



the bushes examined which contained any colonies without the winged 

 mother or where there was the slightest evidence of the previous 

 presence of aphides ; no cast skins from old colonies or damaged leaves, 

 and every indication went to prove that the winged form had just settled 

 upon the trees and begun the formation of colonies. While perhaps of 

 little value as proof, it may also be mentioned that no Sehizoneuras had 

 been observed on Cornus this fall prior to this date or before the swarm- 

 ing of September 15. A number of branches containing colonies were 

 brought in and kept in water for the purpose of following their devel- 

 opment. This was fortunate, as the colonies on the plants out of doors 

 were almost all depopulated a few days later by predaceous insects, 

 so much so thai; the colonies on plants near at hand aud on which I 

 depended for following the species out of doors utterly failed to furnish 

 material for that purpose. Indoors the insects developed rapidly and 

 were followed as closely as circumstances would permit. Molting in 

 these occurred by the 19th, and apparently only one molt occurred 

 before maturity. Only one brood was developed, these becoming sex- 

 ually mature September 25. Both males and females were apterous 

 and copulation took place upon the leaves and also upon the twigs, the 

 females often traveling down the twigs and branches while copulation 

 was in progress. In every case the females seemed to travel down the 

 branches as far as possible before depositing eggs, and great numbers 

 of them dropped into the water in which the branches were kept. In 

 the woods I have been unable to find any eggs whatever under buds on 

 twigs, and so far as the indoor observations go they differ from those 

 recorded by Mr. Weed. Whether this be due to dryness, the insects 

 seeking a place of some degree of moisture, can be determined by com- 

 parisons under varying conditions. 



Two weeks after the swarming of winged lice in the air there was 

 another swarming, though the lice were not so numerous as at the first 

 time. This swarming also followed a rain with subsequent cold. As 

 in the preceding case, examination of Cornus in the woods showed nu- 

 merous winged individuals starting colonies, though at this time in 

 some places it was possible to find the cast skins of previous colonies, 

 all of which, however, so far as I could find, had been destroyed by 

 predaceous insects or other causes. My search for eggs in the woods 

 has been futile, and it would seem that nearly all the colonies were de- 

 stroyed before the maturity of the sexual individuals. I have found, 

 however, oval bodies a trifle larger than the eggs, but resembling them 

 at first sight, though flattened, but which prove to be a small species 

 of Lecanium, apparently undescribed. 



The lice occurring on the roots of grass, and which were placed in 

 breeding jar the 16th, were mostly unaltered on the 19th, but in the jar 

 I found a fully winged specimen, agreeing exactly, so far as could be 

 seen with hand lens, in the living individual, with specimens flying and 

 also with those ou Comus. It was transferred to a leaf of Cornus on 



