Plate 1. 



Pachyccrianthus multiplicatus. 

 Fig. i. Natural size. 



2. Section of three mesenteries with the adjacent parts of the stomatodaeum and column. Ecto- 

 derm of column not shewn. 



3. Section of a portion of a marginal tentacle. 



4. Section of a hemisulcus with adjacent portion of directive mesentery. 



5. Section of craspedoneme (Mesenterialfaden der Flimmerstreifenregion). 



6. Section of cnido-glandular tract ("the simple portion of the mesenterial filament" - "Nessel- 



drusenstreifen", "le filament pelotonne"). 



