HYMENOPTERA 959 



houses in the tropics, clear out the vermin with which they may be 

 infested, and compel the human inhabitants to leave for a time. 



The subfamily is represented in ovir fauna by a single genus, 

 Eciton, species of which occur from North Carolina and Colorado 

 sotithward. Our species, however, do not form large armies, though 

 they hunt in files like the tropical species, and the colonies of some 

 of the species may consist of thousands of individuals. Some of the 

 species are fond of kidnapping the brood of other ants. The females 

 are wingless and much larger than the workers. The workers are 

 pol^Tiiorphic. 



The subfamily CERAPACHYIN^ is represented in our fauna 

 by two genera, Cerdpachys and Acanthostichns , species of which occur 

 in Texas. These genera were formerly included in the subfamily 

 Ponerinae. 



Subfamily PONERIN^ 



The Ponerme Ants 



In the ants of this subfamily the pedicel of the abdomen consists 

 of a single segment and there is a distinct constriction between the 

 first and second segments of the gaster (Fig. 

 1 177). The constriction between the first and 

 second segments of the gaster distinguishes 

 these ants from those other ants in which the 

 Fig. 1177. A ponerid. pedicel of the abdomen consists of a single seg- 

 ment. 



Our representatives of this subfamily are rare or of local occurrence 

 in the North, where they form small colonies, often of a few dozen 

 individuals. They make their nests in the soil or in old logs. As a 

 rule the queens are but little larger and the males but little smaller 

 than the workers, and there is only a single foiin of worker in a 

 species. The pupa stage is passed within a cocoon. These ants are 

 carnivorous, feeding on other insects and do not collect honey-dew. 

 In the South Odontomachus is common, forming large colonies of 

 active ants of large size, under old logs. 



The subfamily PSEUDOMYRMIN^ includes four genera only 

 one of which, Pseudomyrma, is represented in North America. This 

 is a neotropical genus, species of which are found from Florida to 

 Texas, and in southern California. They are very slender ants and 

 make their nests in hollow twigs or other cavities of plants. The 

 larvae are of a remarkable form; the body is long, the head large 

 and ventrally placed, and the thoracic and first abdominal segments 

 are furnished with peculiar exudatory papillas, which form a cluster 

 about the mouth. These ants were formerly included in the sub- 

 family Mynnicinas. 



