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 ITES

show something of interest concerning them. In the first place, it is to be seen that not all the members of the colony are alike. Some, usually the greater number, are small, ordinary, soft-bodied, wingless insects with rounded heads and inconspicuous jaws (Figs. 75 D, 77 A). Others, less numerous, have bodies like the first, and are also wingless, but their heads are relatively of enormous size and support a pair of large, strong jaws projecting out in front (Figs. 75 C, 77 B). The individuals of the latter kind are known as soldiers, and the name is not entirely fanciful, since fighting is not necessarily the everyday occupation of one in military service. The others, the small-headed individuals, are called z'orkers, and they earn their title literally, for, even with their small jaws, they do most of the work of excavating the tunnels, and they perform whatever other labors are to be done within the nest. Both the workers and the soldiers are males and females, but so far as reproductive powers go, they may be called "neuters," slnce their reproductive organs never mature and they take no part in the replenishment of the colony. In most species of termites the workers and the soldiers are blind, having no eyes or but rudiments of eyes. In a few of the more primitive termite genera, workers are absent, and in the higher genera they may be of two types of structure. The large jaws of the soldiers (Fig. 78 A) are weapons of defense in some species, and the soldiers are said to present themselves at any break in the walls of the nest ready to defend the colony against in- vasion. In some speeies, the soldiers have a long tubular horn projecting forward from the face (Fig. 78 B), through which opens the duct of a gland that emits a sticky, semiliquid substance. This glue is discharged upon an attacking enemy, who is generally an ant, and so thor- oughly gums him up that he is rendered helpless--a means of combat yet to be adopted in human warfare. The facial gland is developed to such efficiency as a

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INSECTS