ANIMALS AS FOOD, FOES, OF FFIENDS. 349 



secure themselves from the attacks both of browsing ani- 

 mals and leaf-cutting insects 

 by encouraging the presence 

 of colonies of warlike ants 

 upon them and making pro- 

 vision for their defenders' 

 wants. A very large number 

 of species * protect themselves 

 in this way. For the ants 

 the plants provide (a) nectar, 



Fig. 392. 



Fig. 393. 



Fig. 392. — Bit of a section through the cushion (c, fig. 393) at base of leaf of Cecropia, 

 showing the velvety hairs with which it is covered, and among them the egg-like 

 bodies, rich in proteids and fats, which the ants collect and carry into their nests in the 

 interior of the stem. Magnified about 10 diam. — After Schimper. 



Fig. 393. — Apex of the hollow stem of a young Cecropia. a, the thin spot above a 

 leaf, which at b has been gnawed through by the ants to make their nest in the cavity 

 of the stem ; c, the cushion at base of leaf stalk where food bodies grow. See fig. 39--. 

 Two-thirds natural size. — After Schimper. 



similar to that secreted in the flower, i.e., a watery solution 

 of various sugars, but secreted by nectaries outside the 

 flower; (b) fodder, in the form of hairs (fig. 392), often of 

 peculiar form, richly supplied with nutritive substances, 



* More than three thousand are listed by Delpino. 



