180 BRANCH ARTHROPODA 



slave making has reacted upon themselves, rendering them unable to help 

 themselves. It is a law in all animal life that dependence upon others 

 renders one more dependent, while dependence upon self develops inde- 

 pendent powers. 



The corn-louse ant (Las'ius hrun'neus) is the common small brown ant of 

 our pastures, woods, and meadows. It is of especial economic interest on 

 account of the care it bestows on the corn-root plant-louse. The eggs of 

 the plant-louse are laid in the ant's nest, where they are sheltered during the 

 winter. In the spring the ants place the young aphids upon the roots of 

 certain knot-weeds until the corn has germinated and then remove them to 

 the corn-roots. These aphids do great damage in the Middle West. (See 

 p. 144.) 



(2) Poner'idae is the smallest family in number of species, there being but 

 about twenty-five known in this country, and the least specialized, that is, 

 the least differentiated into castes. The queen and workers are stingers. 

 Their nests are made under stones or logs. 



(3) Myrmic'idae. — This family is characterized by two segments in the 

 peduncle. Usually the queen and workers have stings. The pupae are 

 naked. To this family belongs the tiny " red ant " (Monomo'rium pharao'- 

 nis), which is in reality a light yellow, that is the torment of housewives. 



The agricultural ants (Pogonomyrmex) live in the southern and western 

 states. They, with the exception of one species, live in nests partly under 

 ground, covered with conspicuous mounds in open sunny places. They cut 

 away the grass immediately about the nest. It has been popularly believed 

 that they sow the seed for their food, but Wheeler says that they carry out 

 the debris, which consists of chaff and sprouting grain, and deposit it at the 

 edge of the cleared circle. The seeds often grow and do yield a harvest for 

 their next winter's stores, though not intentionally planted. 



Intelligence. — There is a great diversity of opinion among 

 scientists who have experimented with ants as to the " mental- 

 ity " of these insects. Bethe^ and others hold to a purely me- 

 chanical or reflex theory, while Loeb, Wheeler, and others at- 

 tribute to them reflexes, instincts, and animal memory, and 

 Lubbock and Forel give them a considerable degree of intelli- 

 gence. Comstock says they " think. "^ Whether they are 

 governed by one or all of these attributes, it is surely probably 

 that the mechanical and chemical forces which affect the 

 nervous activities of the ants may also influence those of men, 

 and that if the same rigid experiments and final anah'sos were 

 applied to the various phases of man's activities, there would 

 result quite as many surprises as have accompanied the experi- 

 menting upon insects, indicating that many of his activities 

 are responses to mechanical stimuli, and yet no one doubts 

 that man possesses intelligence. Whether the activities of ants 



» Kellogg, 544. 2 Comstock, 637. 



