298 [September, 



each with its pupa of viridana. Each pupa did not, however, produce 

 a moth. The ichneumon, to which no doubt we shall owe the reduction 

 of the moth to its normal conditions, was well in evidence. 



A week later I was at Ockley near Dorking, where the devasta- 

 tion was almost equally great. A kind friend — Mr. Goodchild, of 

 Stilehurst — drew my attention to what was for a short time a real 

 curiosity. A large and spreading oak, standing well out in an open 

 space where some of the paths converge toward the mansion at Capel, 

 had been chosen by, to all appearance, greater multitudes of the 

 insects than usual ; it had consequently become stripped before the 

 larvaB were full-fed; so soon as food failed they had lowered themselves 

 in thousands to look for more, filling the air with their delicate threads ; 

 when on the ground instinct had evidently guided them to re-climb 

 the tree by the trunk, each, I suppose, leaving its silken thread as it 

 ascended. The result was that the whole trunk of this large tree, 

 with the larger branches, was covered with a thin, white, glistening, 

 silken carpet or film, composed of the threads left as the larvae 

 climbed with those blown by the wind against the tree ; and even 

 when I saw it, after a heavy storm of rain, every sheltered patch of 

 bark was still covered with this wonderful and delicate sheet. From 

 my friend's account, which was fully confirmed by the patches still 

 visible, this tree must, before the rain-storm, have presented a beauti- 

 ful as well as truly extraordinary appearance. 



The moths were then beginning to appear, and one of my 

 daughters who had remained at Haslemere tells me that their 

 multitudes were such that sheltered portions of the road were so 

 covered with the moths as to present a most curious carpeted pattern ; 

 while the clustering upon the oak twigs was as though bunches of 

 sessile whitish blossoms had broken out. Other thousands filled the air, 

 and settled on the clothes of the passers by. Some effort at migration 

 must have been made, for, despite the absence of oak trees here in 

 the suburbs, imagines of this species were common about the limes 

 and poplars in my own and the neighbouring gardens. 



I did not observe this year that the maples had been stripped, 

 though this happens sometimes when T. viridana is too abundant ; 

 but some sallows in the lower parts of the Haslemere woods had been 

 as completely defoliated as the oaks, and, no doubt, by the same 

 agency. 



39, Linden Grove, Nunhead : 

 July IZth, 1896. 



J 



