i9o6] • Wheeler, Habits of the Tent-building Ant. 7 



dried paper-pulp. Under the microscope this resolves itself into 

 bleached particles of Sphagnum moss agglutinated by some secretion 

 from the cephalic glands of the worker ants. Several of these tents 

 are shown in Figs. 2,3, and 4, PI. I, PI. II, and Fig. i, PI. III. They 

 completely envelop the terminal twigs a few inches from the tips and, 

 though fragile, are evidently well protected from the wind and rain 

 bv the needles projecting through and a considerable distance beyond 

 their walls on all sides. Some of the differences in the sizes and 

 shapes of these tents are shown in the figures. The smallest speci- 

 mens are 2.5 cm. long and i cm. in diameter, the largest 4 cm. long 

 and nearly 3 cm. in diameter. Their walls are rarely thicker than 

 ordinary blotting paper and as they are perforated and supported 

 by the needles at a little distance from the surface of the twig, each 

 tent encloses a space obstructed only by the bases of the needles, 

 which thus answer the same purpose as the poles in a veritable tent. 

 As a rule there is but one entrance, a circular hole about 1.5 mm. 

 in diameter usually on one side and near the lower end of the tent, 

 that is, the end nearer the ground or first reached by the ascending 

 files of workers. 



All of the tents contained herds of plump Coccidse, 2—3 mm. in 

 length, which sometimes completely covered the enclosed bark of the 

 twig. There were also a number of pilosa workers busily imbibing 

 the ejecta of their protegees or resting quietly in or among them as 

 if loath to leave the pleasure pavilions. In Figs. 3 and 4, PI. I, two 

 of the tents are reproduced with a large portion of the wall removed 

 to show the extent of the enclosed cavity, the way in which t^e walls 

 are supported by the pine-needles, and the Coccidae clustered on the 

 bark of the twig. 



The striking character of the tents described in the preceding 

 paragraphs leads naturally to the question of their function and the 

 study of the instincts of which they are an expression. There are 

 several possible answers to such a question. We may suppose that 

 C. lineolata builds these structures 



1. for the purpose of preventing the escape of the aphides and 

 coccids to other plants or to other parts of the same plant; 



2. for the purpose of protecting tliese insects from their natural 

 enemies or from other ante : 



3. for the purpose of protecting them from the cold; 



4. for the purpose of protecting themselves from exposure. 



For some or all of these purposes the tents would seem to be most 

 admirable contrivances.' It is probable that the aphides and coccids 



