284 HENRY C. MCCOOK. 



clianiie by the uncomfortable temperature within tent. At 3.45 A. M. 

 I visited the hills to observe the efi'ects of the cold upon the ants. 

 Notan ant was visible on the mounds, on the avenues or the tree-path?. 

 Tapping the hills and stamping upon the sui-rounding stones, which 

 alway.s had brought out a multitude of insects, failed to arouse a single 

 sentinel. I dug beneath the surface of the hill six or eight inches be- 

 fore coming upon ants, and these showed little activity, a sharp contrast 

 with their usual zeal in defence of their domain. In order to be as- 

 sured that the absence of the ants from avenues and tree-paths (never 

 before noticed), was not occasioned by the torpidity or absence of the 

 aphides, 1 examined one of the most largely patronized feeding grounds, 

 the white oak beside the stone fence, already referred to as frequented 

 by the inmates of hill PI. II. I mounted the wall, and turned the 

 lantern-light upon the overhanging branches. The aphides were in 

 their places surrounded and covered by groups of ants in a semi-torpid 

 condition. Ants in the same estate were hanging all around the inter- 

 vening sections of the bough. The frost had evidently surprised them 

 at their feast, and left them frigid upon the spot. Some of the insects 

 had their abdomens well filled, as the honey-dew showed transparent in 

 the lantern-light. At 8.40 A. M. a few sluggish movements were noted 

 on the hill. On the avenues (in the shade), there were a number of 

 ants, the great majority being homebound, and of these a large pro- 

 portion repletes. At 8.50 the tree-path, then in the sunshine, was 

 covered with ants, the majority repletes and very full. At 9.5 the 

 ants were in their normal condition in the branches, then ^n full 

 sunlight. 



Winter Habits.— I was greatly desirous of knowing the condition 

 and habits of the ants during winter. During a visit to Altoona, Oct. 

 26, 18TG, I took occasion to drive over to Camp Riddle, some six miles 

 distant. It was a raw, cold day, with occasional flakes of snow. The 

 ants were confined to the mounds, only a few stragglers appearing upon 

 the surface in a rather inactive condition. Those within the hills, 

 however, were quite active and were able to spring upon the hand and 

 inflict the usual wound. They all were much less affected by the cold 

 than during the frost of the summer. The aphides were hanging upon 

 the branches, unattended, black and with distended abdomens. Signs 

 of work were seen on one hill ; warts raised over several gallery-doors, 

 as though a new story had been begun. 



The solution of this inquiry into winter economy was referred to 

 Mr. Kay, who on the 14th Feb., 1877, with Mr. Knox, a friend, visited 

 the colony at Pine Hill. He had been furnished with various points 



