In the vast majority of winged insects the terminal part of the genital system (vagina and ductus ejaculatorius) is unpaired and ectodermal.
B, anterior portion more highly magnified (from Marshall and Hurst, after Sommer); cs, cirrus sac; d, ductus ejaculatorius; f, female aperture; o, ovary; od, oviduct; p, penis; s, shell-gland; t, anterior testis; u, uterus; va, vp, vasa deferentia; us, vesicula seminalis; y, yolk-gland; yd, its duct.
C, genital sinus and neighbouring parts (from Sommer); a, ventral sucker; b, cirrus sac; c, genital pore; d, evaginated cirrus sac: e, end of vagina; f, vasa deferentia; g, vesicula seminalis; h, ductus ejaculatorius; i, accessory gland.
The word usage examples above have been gathered from various sources to reflect current and historial usage. They do not represent the opinions of YourDictionary.com.