124 ENTOMOLOGY 



the two ducts enter a common evacuating duct (vagina or ejaculatory 

 duct). The vagina commonly opens just behind the eighth abdominal 

 sternite, and the ejaculatory duct behind the ninth 



s v 



FIG. 181. Reproductive system of male FIG. 182. Reproductive system of 



beetle, Melolontha. a, accessory gland; c, copu- male Lepidoptera. a, accessory gland; 



latory organ; d, ejaculatory duct; s, seminal d, ejaculatory duct; t, united testes; v, 



vesicle; t, testis; v.vas deferens. After KOLBE. vas deferens. After KOLBE. 



Homologies. As in other animals, the reproductive organs are 

 homologous in the two sexes. Thus; 



MALE FEMALE 



Testes = Ovaries 

 Seminal ducts = Oviducts 

 Ejaculatory duct = Vagina 



Seminal vesicle = Seminal receptacle . 

 Accessory glands = Accessory glands 

 Penis and accessories = Ovipositor 



Male Organs. Each testis, though sometimes a single blind tube, is 

 usually a group of tubes or sacs (Fig. 181), testicular follicles, which open 

 into a seminal duct (vas deferens) . In most Lepidoptera the testes are 

 secondarily united into a single mass (Fig. 182) as also in Locustidae. 

 The two seminal ducts enter the common ejaculatory duct, which termi- 

 nates in the intromittent organ, or penis. Often each vas deferens is 

 dilated near its mouth into a seminal vesicle, or reservoir; or there may be 

 only a single seminal vesicle, arising from the common duct. One or 

 more pairs of glands opening into the vasa deferentia or the ductus 

 ejaculatorius secrete a fluid which mixes with the spermatozoa and 

 oftentimes unites them into packets, known as spermatophores. 



All these parts are subservient to the formation, preservation and 

 emission of the spermatozoa. These minute, thread-like bodies (Fig. 



