146 



F. H. STEWART. 



by two canals with the exterior aud by two canals with the 

 two uteri. 



This condition and that found in 0. vulgaris suggest at 

 once a comparison with Trematodes. The former reminds us 



Text-fig. 8. 



Lc 



of Laurer's canal as it occurs in Malacocotyleans, the latter of 

 the genito-intestinal canal of Heterocotyleans. The diagrams 

 (text-figs. 8, 9) illustrate the point better than much writing. 

 The diagrams of the Trematodes are copied from the article 

 in Eay Lankester's 'Treatise on Zoology,' Pt. IV, p. 87. 

 Text-fig. 8 a represents diagrammatically a transverse sec- 



Text pict. 9. 



Germ G lc. 



tion through 0. fuscus. The " Eohrenformige Organ " (e.g.), 

 with its ducts, is shown. Text-fig. 8 h -/epresents a Malacoco- 

 tylean. (rcj-m is the gcrmarium, L. c. Laurier's canal. Text- 

 fig. 9 a represents 0. vulgaris, and shows the gonenteric 

 canals, to be compared with the genito-intestinal canal {g. i. c.) 

 of the Heterocotylean (text-fig. 9 &). 



In text-figs. 8 a and 9 a the two uteri and vaginae are, for 

 fairness of comparison, represented as if they lay side by side. 



