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Page:Popular Science Monthly Volume 7.djvu/274

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260
THE POPULAR SCIENCE MONTHLY.

head. This frontal eye is totally wanting in the other workers, and is not known in any other kind of ant. Their special functions are unknown. None of this species are pugnacious.

The work of reproduction begins with the rainy season. The union probably takes place in the night, for in the morning the neighborhood of the nest will be strewed with the females, and the dead bodies of the males, the former already fertile, from whom the workers make it their duty to tear away the wings. The true females are incapable of attending to the wants of their offspring; and it is on the poor, sterile workers, who are denied all the other pleasures of maternity, that the care devolves. The successful début of the winged males and females depends likewise on the workers. Great activity reigns in an ants'-nest on the exodus of the winged individuals. The workers clear the roads of exit, and show the most lively interest in their departure, although it is highly improbable that any of them will return to the same colony. They are of large size, the female measuring two and a quarter inches in expanse of wing; the male is not much more than half the size. They swarm in vast numbers, but are so eagerly preyed upon by insectivorous animals that but few of the impregnated females escape the slaughter to found new colonies. An immense amount of labor would be saved to the ants, if, instead of raising annually myriads of winged males and females to perish, they raised only a few wingless males and females, which, free from danger, might remain in their native nests; and, as Fritz Müller says, he who does not admit the paramount importance of intercrossing must of course wonder why the latter manner of reproduction has not long since taken the place, through natural selection, of the production of winged males and females. But the wingless individuals would of course have to pair always with their near relatives, while by swarming a chance is given for the intercrossing of individuals not nearly related.

Fig. 2.—Saüba Ant, Female.

Resembling the saüba, in being vegetable-feeders, are the harvesting-ants (Atla stnictor, A. barbara, Pheidole megacephala etc.). It has been a fashion among naturalists to set down as pure invention the accounts by classical writers of the accumulation of cereals by ants for winter consumption, and to assume that the Biblical injunction to