Page:Insects - Their Ways and Means of Living.djvu/190



perhaps would migrate to some other part of the country; here they would have children of their own, and the new fourth géneration would be unlike any of the three pre- ceding; this generation would then produce another, again different; and the latter would return to the home town of their grandparents Cm Nx and great-grandparents, and \ / here bring forth children that \ .a would grow up in the like- / ness of their great-great- great-grandparents! This seems like a fantastic tale of fiction, too preposterous to- be taken seriously, but it is a commonplace fact among the  aphids, and the actual gen- / ealogy may be even more Lb complicated than that above outlined. Moreover, the Fro. 9 o. Cross-section through story is hOt yet complete, the base of the beak of an aphis, for i't musr be added that all (From Davidson) Theouter sheath of the b«ak is the the generations of the aphids, labium (Lb), covered basally by except one in each series, are the labrum (Lin). The four in- closed bristles are the mandibles composed entirely of females (Md) and the maxillae (Mx), the capable in themselves of re- latter containing between rhem a food canal (a) and a salivary canal production. In warm " cil- (b). Only th« inner walls of th« mates, it appears, the female labrum and labium are shown in thesection succession may be uninter- rupted. How insects do upset out generalizations and our peace of mind ! We have heard of feminist reformers who would abolish men. With patient scorn we have listened to their predictions of a millenium where males will be unknown and unneeded--and here the insects show us not only that the thing is possible but that it is practicable, at least for a certain length of time, and that the time can be in- definitely extended under favorable conditions.

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