i6o 



UNSEGMENTED "WORMS." 



Thence they are expelled by an ejaculatory duct, which passes through 

 a muscular protrusible penis. The retracted penis and the seminal 



Fig. 71. — Reproductive organs of liver fluke. 

 — After Sommer. 



f. Female aperture. 

 s.v. Seminal vesicle. 

 y.gl. Diffuse yolk glands. 

 sk.g. Shell gland. 

 v.d. Vas deferens. 

 T. Testes (anterior). 



ov. Ovary (dark). 

 ut. Uterus. 

 c.s. Cirrus sac. 



p. Penis. 



m. Mouth. 



£■. Anterior lobes of gut. 



vesicle lie in a space or "cirrus sac "between the ventral sucker and 

 the external male genital aperture. The ovary is also branched, but 

 less so than the testes. The ova pass from its tubes into an ovarian 



