PHYLUM ARTHROPODA 369 



Vespa, builds a more elaborate nest than that of Polistes. It 

 consists of a series of combs one above the other, and is sur- 

 rounded by a paper covering with an entrance near the pointed 

 lower end. 



The ants (FoRMiciD^:) constitute in many ways the most 

 remarkable group of insects in the world. Their adaptations for 

 the complex social life that the^ lead are very wonderful. A 

 colony, as in the social bees and wasps, contains a queen, males, 

 and workers. The workers may be modified as large or small 

 workers, or as soldiers. Ants usually live in tunnels in the ground, 



FIG. 312. Honey ants and leaf-cutting ants 

 (From Brehm.) 



or in wood, or in the hollow stems of plants. Beetles and other 

 insects live in ants' nests. The honey-ant, Myrmecocystus (Fig. 

 312, i) is a peculiar form. Some of the workers cling to the roof 

 of the mound-like nests and serve as reservoirs for the storing of 

 a sort of honey until it is needed by the colony. The leaf-cutter 

 ants (Fig. 312, 2) of the genus A tta ((Ecodoma) have a peculiar 

 method of securing food. Certain workers cut out pieces of 

 leaves and carry them to the nest, where the other workers pack 

 them into balls on which they cultivate a fungus, Rozites gongy- 

 lophora. The ants regulate the growth of this fungus in such 

 a way that it produces white masses which serve as food for the 

 colony. 



2 B 



