88 SECOND REPORT OF THE STATE ENTOMOLOGIST. 



elm would, as the result, be unusually tender. The particular feeding 

 ground of many of the lepidopterous larvce is known to be selected only 

 after repeated tastings and rejections of such portions of their food- 

 plant as they traverse, and a final acceptance of that most agreeable to 

 them. By a process like this the Orgyia may have made the discovery, 

 that just at the commencement of the new growth, as the result of the 

 seasonal conditions above mentioned, there was concentrated in the 

 tender bark nutriment far more acceptable to it than that offered in the 

 leaves, upon which alone it had hitherto been accustomed to feed. As 

 tiie bark hardened with the advancing season, it would cease to be 

 desirable for food. 



During my absence from the city for most of the months of July and 

 August, the following observations upon the falling tips and the Orgyia 

 were made, at my request, by Mr. W. W. Hill : 



July 6, Tips of four to six leaves falling, larvae — some spinning. 



July lo. Many larvae spinning — a female moth ovipositing. 



July II. A few tips observed. 



July 12 and 13. Tips falling fast after a heavy rain — moths ovi- 

 positing. 



July 14-21. Tips falling — male and female moths observed. 



July 22-31. Larvae, cocoons and moths — many tips falling. 



Aug. I. Larvre, cocoons and tips observed. 



Aug. 2-1 1. Tips falling, but no larvae or moths seen. 



Aug. 18. Tips still falling. 



On my return to Albany for a few days, on the 21st of July, 

 most of the tips then falling and many of those upon the ground 

 presented a new feature. The breaking, instead of being at the base 

 of the girdling, just above the commencement of the new growth, was, 

 in these, at the preceding node, covering the growth of the former year, 

 as represented in Fig. 12. As a rule, the twigs showed a greater diameter 

 at their decorticated portion, compared with those of the earlier fall, and 

 the leaves attached to them had been all more or less eaten by the Or- 

 gyia. Their greater strength had permitted them to remain longer upon 

 the tree, and until the death of the preceding internode, which soon fol- 

 lowed the arrest of the circulation — its starvation ensuing — it being 

 unprovided with leaves through which a circulation could still be main- 

 tained. When dead, a slight movement of the branch by the wind, or 

 even the weight of the terminal leaves would be sufficient to disconnect 

 it at its lower and weaker node. In a few instances, as shown in Fig. 

 13, where the girdling had been at a little distance above the node mark- 

 ing the commencement of the present year's growth, the separation had 

 been at this point, while others separated in this manner, instead of the 



