Stephenson — Certain Actiniaria collected off Ireland. 163 



Fig. 



4. Actinernus saginatus. Diagram of part of a T. S. of a tentacle, to show 



general relations of parts, and, as nearly as I 

 can get it, the general appearance of the muscle - 

 layer under a low power. Oc. 3. Obj. -f. 



5. „ „ Detail of the whole width of the upper tail-end of 



the sphincter. Obj. 1|. 



6. „ „ Diagram to show form and position of whole 



sphincter. Enlarged only a few diameters. 



7. „ ,, Detail of a small portion of the longitudinal muscle- 



layer of the tentacle-ectoderm, with its surround- 

 ing nerve-layer. Oc. 3. Obj. ■£. 



10. „ „ Parietal muscle of a fair-sized mesentery. Oc. 3. 



Obj. 1*. 



8. Clwndrodactis coccinca. Parietal muscle of a directive mesentery. Oc. 3. 



Obj. |. 



9. „ „ Most of the pennon of a primary mesentery. 



Obj. 1|. 



11. „ „ Part of T. S. of a tentacle. Oc. 3. Obj. f. 



12. „ „ Whole directive mesentery, low magnification. 



17. „ „ T. S. of part of oral disc. Obj. 1^. 



(re - x are a pair of large mesenteries ; y is one of a 

 smaller pair.) 



18. „ „ Detail of small portion of radial musculature of oral 



disc. Oc. 3. Obj. |. 



13. Clwndrodactis pukhra. Parietal muscle (of a smaller mesentery than that 



figured for C. coccinca). Oc. 3. Obj. § . 



14. „ „ Muscular part of a third cycle (?) mesentery. 



Obj. 1J. 



15. „ „ T. S. of acontium. Obj. I3. 



16. „ „ Part of transverse section of a tentacle. Oc. 3. 



Obj. f 



19,20. Clwndrodactis duplicata. Three small portions of detail of radial mus- 

 culature of oral disc. Oc. 3. Obj. |. 



21. „ „ Detail of a portion of the sphincter, just below 



its upper end. Obj. 1|. 



Plate XIX. 



1, Carlgrenia desiderata. Muscular part of a macromesentery, and the whole 



of the adjacent micromesentery. Obj. 1£. 



