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Fig. 190.—1, sting and poison sac of the honey-bee: GD, poison gland; Gb, poison reservoir; D, accessory gland; sh, sheathing style or sting-“feeler”; Str sting; Ba, sheath; Q, quadrate plate; O, oblong piece; W, angular piece; B, base of the sting and stylets; Stb′, Stb″, the two barbed stylets or darts. 2, sting seen from the ventral face: lettering as in the other figure.—After Kraepelin, from Perrier.

In the ants, according to Dewitz, the genital armature is derived from imaginal buds situated on the under side of the seventh, eighth, and ninth abdominal segments. Bugnion has observed the formation of six imaginal buds of the genital armature in the larva of a chalcid (Encyrtus, Figs. 41, 42, 191, q1, q2, q3), the transformation of the central part of these structures into small digitiform pads, then the division of the two intermediate buds into four (?) (Fig. 191, B, q2), but was unable to trace their farther development.

The subject still needs farther investigation, since certain observers, as Haase, and, more recently, Heymons, do not believe that they are homologues of the legs, but integumental structures, though of somewhat higher value than the style of the base of the legs of Scolopendrella and Thysanura; but it is to be observed that as yet we know but little of the embryological history of these styles.