190 ANATOMY AND PHYSIOLOGY 



coating to the eggs before they are extruded. This 

 varnish, however, is more commonly imparted to 

 them in the wider part of the duct, formed by the 

 union of the tubes from the two branches of the 

 ovaries. This common duct is sometimes called the I 

 egg-canal. It is of greater diameter than the ovi- j 

 duct and frequently distended in the middle where j 

 the egg occasionally remains stationary for a time 

 before being expelled. Of the various appendages ! 

 of this portion of the egg-conduit, the most import- 

 ant are the sperm-reservoir, (Spermaiheca) gluten 

 secretors, and the poison vessels of the aculeate 

 Hymenoptera. The former is a purse-shaped ap- 

 pendage or distention of the duct, destined for the 

 reception of the male influence during copulation 

 and, according to Herold, the eggs are impregnatec 

 in passing it, for it is situate on the upper side, am 

 whenever it opens the sperm flows into the duct 

 The gluten secretors are commonly more slender 

 and of a vascular structure, performing the office o 

 a gland. The liquid they secrete is white, and i 

 envelopes the eggs in their passage. Their situation 

 is very close to the sperm reservoir. The poison 

 vessel of the Hymenoptera is an ovate bladder wit] 

 a narrow duct appended to it, which discharges the 

 contents into the sting. 



The vagina is simply the terminating portion o 

 the evacuating duct ; a short straight tube, generall) 

 a little narrower than the common branch of th 

 oviduct. When an ovipositor exists, the vagina 

 tube opens directly into it, forming a continuous 



