Description of Some Japanese Polyclad Turbellana 



giving off numerous lateral intestinal branches; these repeatedly 

 subbranch and anastomose, bringing about a network of rather 

 narrow branchlets. 



Three apertures open one behind another in the median lino 

 between the pharyngeal chamber and the posterior body end. The 



7 middle and the 



hindmost apertures 

 are respectively the 

 functional male and 

 female openings, 

 while the foremost 

 may be called the 

 duplicate male aper- 

 ture. The functional 

 male aperture (text- 

 fig- 7, 8, £) leads 

 into the ciliated an- 

 trum musculin urn 

 (am), into which the 

 small penis (p) pro- 

 jects vertically from 

 above. The ejaeu- 

 latory duct (cd). 

 shortly after leaving 

 the penis, divides 

 into two ducts, dorsal 

 and ventral. The 

 former joins the 

 anteriorly directed 

 muscular prostate 

 (pr), while the latter 

 passes obliquely 

 downward to bifur- 

 cate into two seminal canals (sc), without forming a seminal vesicle. 

 The duplicate male organs bear a close resemblance to the 

 functional described above. The external aperture (£') leads into 



pr 



pr 



ed # P s v .£ vd 



Textfig. 7. Diagrammatic representation of the genital end- 



organs of B. diversa, as seen from the ventral side, 

 lextfig. 8. Semidiagrammatic genital end-organs of B diversa 

 in sagittal section. 

 i intestine, p' duplicate penis, pr' prostate-like organ, 

 s spiral coils of vagina, sv' seminal vesicle-like organ, 

 uu unpaired uterine duct, v vagina, vd vaginal duct, 

 $' duplicate male genital aperture. 

 Other letters as in textfig. 4. 



