206 



PROCEEDINGS OF THE MAIACOLOGICAL SOCIETY. 



The initial tract of the free oviduct (o.d.) is of very small calibre, 

 being only a trifle larger than the vas-deferens (v.d.). It does not 

 open directly into the vagina (v.), but into what must be regarded 

 as the base of the spermatheca duct, which latter is separated from 

 the vagina by a well-marked constrictor muscle situated immediately 

 below the oviducal aperture. The interior of the vagina is longi- 

 tudinally plicated, the plicae being very strongly developed, and the 

 interior of the spermatheca is also longitudinally plicate, but much 

 more finely so than the vagina. 



f— ZO 9n <*n. — | 



Genitalia of Thersites bipartita (Fer.). 



The muscular penis (p.) is sharply bent upon itself at the point of 

 insertion of its retractor muscle (r.p.). At the junction of the penis 

 and epiphallus (e.) there is a thin-walled hemispherical saccular out- 



