110 Myemecophily 



warding off browsing mammals and driving away the 

 destructive leaf-cutting ants. He noticed that the 

 standing army had barracks in the hollow thorns, 

 and that they were well victualled by the plant. At 

 the base of the midrib of each beautiful leaf there is 

 a crater-shaped gland, secreting a honey-like liquid, 

 of which the ants are very fond. Moreover, on the tip 

 of each of the leaflets there is a little yellow body, like 

 a golden pear, about a twelfth of an inch in length. 

 When these little bodies are ripe the ants collect them 

 and carry them into the hollow thorns. An ant trans- 

 porting a single golden pear is as heavily laden as 

 a man carrying a large bunch of plantains. "Belt's 

 bodies," as they have been called, are very nutritious ; 

 they contain protein material, sugar, and oil globules. 

 There is no doubt that Belt, like Delpino about 

 the same time, had the idea of a mutually beneficial 

 partnership between the ants and the acacias. He 

 thought that the "ant-loving" acacias had become in 

 certain ways specially adapted to secure the per- 

 sistent presence of their bodyguard of ants, just as 

 many flowers are adapted to secure cross-pollination 

 through the agency of their insect visitors. "Habita- 

 tions full of food are provided for the ants to com- 

 mence housekeeping with; and cups of nectar and 

 luscious fruits await them every day." As a shrewd 

 observer, however, Belt could not but notice the 

 other side of the picture, conspicuous in the dry 

 season. For then the glands cease to secrete sweet- 

 ness, no fresh food-bodies are produced, the leaves 

 of the acacia fall off, there is great scarcity among 



