Plate V. 



Fig. i 6. Ceriantheopsis americanus. Figs. 7, 8. Arachnactis albida. 



Figs. 9, 10. Botrucnidifer norvegicus. Fig. n. Cerianthus lloydii. 

 Fig. i. Section of a craspedoneme of a craspedion some way from the extremity. 

 2. Similar section nearer the base of the craspedoneme. 



3. Section of a portion of a fertile mesentery in the region of the sexual organs, together with 



craspedion. 



4. Section of the aboral portion of an hemisulcus. The hemisulcus is the part shewing cilia. 



5. Part of the second protomesentery in the craspedoneme and cnido-glandular tract region. 

 6. Part of a mesentery with a craspedoneme of the craspedion region. 



7. Section of a portion of a mesentery with a craspedion in the oral portion of the latter. 



8. Section of a portion of a young specimen in the upper part of the hyposulcus, to shew that 

 the directive mesenteries exhibit the same arrangement of the musculature as the rest of 

 the mesenteries. 



9. Section of filament in the ciliated tract region a little below the stomatodaeum. 

 - 10. Part of a mesentery with a craspediou. 



ii. at the aboral end of the animal. 



