REPORT OF THE ENTOMOLOGIST. 259 



made durijig the past season, may here be given as supplementing that 

 paper. 



In Washington during the i)ast winter the trunk form has maintained 

 itself upon the trunk tfiroughout the v/hole winter without the interven- 

 tion of a winter egg, and the root form has done the same. The winter, 

 however, has been an unusually miid one. 



The winter e^g was found on several occasions during the winter in 

 crevices of the bark over which a colony had been stationed during the 

 summer. It was a rather long ovoid, measuring .322""° (.12 "» inch) 

 in length and was very similar to the winter egg of ColopJia tdimcola 

 (Fitch), as described by Kiley in Bulletin No. 1, Vol. V, Hayden's Survey. 



This egg was laid, as Professor Thomas supposes, by a wingless fe- 

 male, difleiing from the ordinary agamic form to a certain extent. 

 These females we only know from finding their skins around the win- 

 ter egg, since they often die without depositing it. The males we have 

 not seen. 



We would take exceptions to the following statement in Dr. Thomas's 

 article : 



So far as the method of propagation is concerned, it has been shown by Dr. William 

 M. Sniith, of Kerf York, that it differs slightly from the true Aphides, in that the young 

 larva ])roduccd by the agamic females are inclosed in the thin egg-shaped covering 

 heretofore mentioned, from which fchey have to free thernaelvea in a manner analogous 

 to hutching. The remains of this covering may often be seen attached to the tip of 

 the abdomen, and is doubtless the supposed cottony secretion alluded to by Dr. Fitch 

 in his description of the young larvae. 



Mr. Howard has repeatedly watched the birth of the young of the 

 wingless agamic females, and positively states that they are born with- 

 out the enveloping pellicle or j)seudovum. While the head and its ap- 

 liendages.were still within the mother, he has seen the legs kicking vig- 

 orously outside. Judging fiom analogy, however, the young from the 

 winged vivii)arous females would be bom within a pseudovum, and it 

 was ]3robably these which Dr. Smith observed (we have no information 

 as to where the paper was published), and from which he has drawn too 

 hasty a conclusion. In the births which were observed, more or less 

 of the waxy (not cottony) excretion was observed at the tip of the abdo- 

 men of the young louse from the moment that its abdomen was percep- 

 tible, thus showing that Dr. Fitch was not necessarily mistaken on this 

 point. 



That the above ground colonies are usually started by migrating indi- 

 viduals from the roots or from eggs laid near the ground we consider as 

 probable, since a regular upward progression was observed through the 

 summer, the suckers being first affected by young lice, which were seen 

 to issue from the ground, and the higher parts of the tree at. a later pe- 

 riod. When working upon suckers, the little colonies seemed prefer- 

 ably to gather in the axils of the leaves, soon causing the leaves 

 to fall off. They were also almost invariably upon the tender and 

 greener side of a shoot, rather than upon the brown and more weather- 

 beaten side. 



As regards the natural enemies of the woolly louse, perhaps the most 

 effective are the spiders, many of them spinning webs dii-ectly over a 

 colony of lice and living at their ease, taking their food when they de- 

 sired. The ntxt in efficiency were the chalcid liics lEHopUilus mail Hald.) 

 Plate VI, fig G.) 



The root louse syrphus fly (presumably the Pipka radicmn of Walsh 

 and 1 viley), has also been found in considerable numbe rs. That the eggs 

 of tL'is fly are laid in the midst of the waxy escretioa and not upon the 

 bark of the tree, is shown by the fact that among a niunber of Uce which 



