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Those authors who have examined the elements of the ovipositor, and regard them as homologues (homodynamous) of the limbs, are Weismann (1866), Ganin (1869), Packard (1871), Ouljanin (1872), Kraepelin, Kowalevsky (1873), Dewitz (1875), Huxley (1877), Cholodkowsky, Bugnion (1891), and Wheeler (1892).

As shown, then, by our observations and those of Dewitz (Figs. 189 and 192), the rudiments of the ovipositor consist of three pairs of tubercles, arising, as Kraepelin and also Bugnion (Fig. 191) have shown, from three pairs of imaginal discs, situated respectively on the seventh, eighth, and ninth uromeres, or at least on the three penultimate segments of the abdomen. With the growth of the semipupa, the end of the abdomen decreases in size, and is gradually incurved toward the base (Fig. 193), and the three pairs of appendages approach each other so closely that the two outer ones completely ensheath the inner pair, until a complete extensible tube is formed, which, by the changes in form of the muscles within, is gradually withdrawn entirely within the body.