The Morphology of the Ovipositor of Draeculacephala

Abstract

The ovipositor of Draeculacephala mollipes (Say) is carried in a longitudinal receptacle (Pl. I, Fig. 8, a) in the caudoventral part of the abdomen. It consists of two pairs of chitinous valvulae (Pl. I, Figs. 1 and 2), which have come to lie mostly in the same caudocephalic plane. The anterior pair (Pl. I, Fig. 1), arising from the seventh sternite, has assumed the lateral or outer position and embraces most of the median pair (Pl. I, Fig. 2), which articulates with the eighth sternite. A third pair of valvulae (Pl. II, Figs. 1,1) serves only as a sheath for the ovipositor proper, and arises from the eighth segment behind the posterior or median valvulae. A set of muscles (Pl. I, Fig. 8, c, c) near the apex of the abdomen probably serves to open the receptacle along its ventral edge and permits the ovipositor to assume its functioning position.