PHYLUM PLATYHELMINTHES 



•3i 



conspicuous structure, owing to its being filled with the 

 dark biliary matter on which the fluke feeds. It divides 

 almost immediately into two main limbs, right and left, and 

 from each of these are given off, both internally and ex- 



FiG. 69. — DiStomum hepaticum. Internal organisation. General view of the 

 anterior portion of the body, showing the various systems of organs as seen from 

 the ventral aspect, ej\ ejaculatory duct; f, female reproductive aperture; int, 

 anterior portion of the intestine (the rest is not shown) ; od, commencement of 

 oviduct; ov, ovary; /, penis; ph, pharynx; sh, shell-gland; te, testes; ut, 

 uterus; vd x , left vas deferens; vct 2 > right vas deferens; vtt, lobes of vitelline 

 glands; vs, vesicula seminalis. (After Sommer.) 



ternally, a number of blind branches or caeca, those on the 

 inner side being short and simple, while those on the outer 

 side are longer and branched. The two limbs of the intes- 

 tine, with their branches, thus form a complicated branching 



