INVERTEBRATA. 



369 



process, the penis or cirrus, which can be protruded through 

 the male aperture, and which is contained in a muscular 

 sac, the cirrus sac. 



The ovaries are a single pair of organs, each consisting 

 of a number of branching tubes, which run from the lateral 

 region in the posterior part of the proglottis to open into 

 a central oviduct. The latter is connected posteriorly with 



Te-~ . 



Fig. 190. PROGLOTTIS OF Taenia solium MAGNIFIED TO SHOW THK GENERATIVE 



ORGANS. 



Te, testes ; V.d., vas deferens ; Ut, uterus ; Ot, ootype Vt, vitelline glands ; N, 

 nerve ; Ex, excretory tube : only one pair of these is shown ; Ov, ovaries ; Od 

 oviduct. 



a small spherical chamber called the ootype, surrounded by 

 small glands which secrete the egg-shell, and this ootype 

 receives posteriorly a short duct from the single vitelline 

 gland, a transversely elongated mass of lobules near the 

 posterior margin of the proglottis. From the ootype is 

 given off a wide straight tube, which runs forward through 

 the middle of the proglottis : this serves for the retention 

 of the completely formed and fertilised eggs, and is called 

 the uterus. From the ootype the oviduct runs parallel to 

 the vas deferens to the female opening which adjoins the 

 ZOOL. 24 



