Aiidraliari k'art/nvorms. 24) 



Fig. 21. — Section of opening of nepliridiuni of Jl\ coora?iiensis to 

 exterioi-, sliowing ;irrangeinent of mu.scles, and the 

 gradual change in character of the epithelium from 

 the ordinary exteiiial cells to the flattened cells 

 lining the vesicle. 



22. — Fletcherodrilus iinicus, v. major. Extei-nal, showing 

 positions of openings of the nephridia to the 

 exterior, with regard to the setae. 



23. — Diagrammatic drawing of same, to show six nephridia 

 in situ on left-hand side of body, with the position 

 of funnel, vesicle, coils and opening to exterior in 

 relation to the setae. 



2 J:. — Drawing of left-hand nephridiuni of segment 6 in situ, 

 showing relatively small size of the vesicle, whicli 

 is thick-walled. 



25. — Drawing of a left-hand nephridium near posterior end 

 of body in situ, showing large thin-walled vesicle, 

 and relation of coils of nephridium to it. 



26. — Diagram illustrating description of nephridia of .same, 

 with the various parts lettered. 



REFERENCE LETTERS. 



Roman numerals indicate position of setae, numbering in 

 order from the nerve cord towards dorsal poi'e. 

 Xumbers refer to numbers of segments. 

 Arrow points to anterior end. 



Nephridium opening ventrally opposite 2nd .seta 



Alimentary canal 



Nephridium opening ventrally opposite 4th seta 



Cells forming funnel 



Cubic cells lining entrance to intracellular duct 



Connective tissue containing ducts from mega- 



nephridia 

 Cilia 



Marginal cells of funnel 

 Nephridial coils 

 Pigmented coil of nephridium 



