Marshall—On the Anatomy of the Dragonfly. 
781 
Each ovary consists of a great many ovarian tubules which 
lie side by side closely packed together. The ovaries are 
changed very greatly in size by the growth of the oocytes; in 
some specimens they are but little larger than the testes while 
in others the entire abdominal cavity is nearly tilled with them. 
The terminal filaments of the ovarioles lie nearly parallel to 
the longitudinal axis of the oviduct and along its inner and 
in part ventral surface. 
Each ovarian tubule (fig. 46) has, distally, a long and thin 
terminal filament. This is followed by a small terminal cham¬ 
ber in which the youngest oocytes are found and these, passing 
backward in the tubule, increase in size, very soon to become 
arranged in a single row, this linear arrangement persists 
until the end. Proximally there is a short basal stalk through 
which the oocytes pass before entering the oviduct. In Lihel- 
lula Jf-maculata there are no terminal or other food chambers. 
The follicular epithelium is rather thin over all parts of the 
tubule; it, as usual in insect ovaries, consists of a single layer 
of cells except between the egg chambers. 
The two oviducts, passing back and converging towards a 
common median line, finally join to form a short; oviductus 
communis. This lies ventral to the seminal vesicles, continues 
but for a short distance, and then passes into the vagina (fig. 
49, Vg). In section the common oviduct shows the presence 
of a thin layer of longitudinal muscles which is absent in the 
vagina. Besides this layer of muscles both the common ovi¬ 
duct and the vagina have at either side a considerable mass 
of muscles (fig. 55). 
The vagina, as already mentioned, is very irregular in shape, 
the wall is longitudinally folded and two of these folds are much 
larger than any of the others. The two larger folds can be 
seen in a dissection in which the vagina is cut open longitudinal¬ 
ly (fig. 47) or in transverse sections. In this latter case the 
folds may come from near the ventral wall of the vagina or 
may have their origin at some place on the lateral walls (fig. 
54). The wall shows a thick cuticular layer with a notice¬ 
able lamellate structure. This layer varies greatly in thick- 
