EXPLANATION OF PLATE XVIII. 



Eyalonema marfahamense. F. E. Sch. 



Fig. 1. Oblique lateral view of a specimen. Nat size. 



Fig. 2. Obli(]ue view of the lower end of a specimen. Nat. size. 



Fig. 3. Arrangement of the spicnles in a transverse section of the upper, 

 lateral margin, vertical to the surface. x 50 (combined figure). 



Figs. 4-7. Mesamphidiscs. x 300. 



Fig. 8. A terminal disc of a micramphidisc, seen from above. x 300. 



Fig. 9. Dermal pinule. x 300. 



• Fig. 10. Marginal spicule. x 300. 



Fig. 11. Parenchymal oiyheiactiue. x 300. 



Fig. 12. Silica-pearl. x 100. 



Figs. 13 and It. Parenchymal diactines from the neighbourhood of the 

 axial spicular fibre. x 50. 



Figs. 15-17. Shorter raacramphidiscs. x 100. 

 Fig. 18. Longer macramphidisc. 100. 



