PLATE XLIL 
PAGE 
Figs. 1, 2. Sphinctrella gracilis, . . .89 
Figure 1. Microxea, spirally ridged ; x 292. 
„ 2. Spiraster; x720. 
Figs. 3, 4. Sphinctrella ornata, . . .90 
,, 3. Tried, with, spirally arranged ridges on the actines ; x 292. 
„ 4. Spiraster ; x 720. 
Figs. 5-11. Amphius huxleyi, . . .178 
,, 5. The sponge ; nat. size. 
„ 6. Oxea; x 200. 
„ 7. Amphiasters ; x 720. 
8. Longitudinal median section through a lobe of the sponge, showing the 
cloaca ; nat. size. 
„ 9. Section at right angles to the surface, to show the general arrangement 
of the canals and spicules ; x 7. 
„ 10. Tangential slice from the surface, showing the pores and oxeas disposed 
tangentially beneath the epithelium ; x 180. 
„ 11. Section at right angles to the surface, passing through a pore-sieve, 
and the underlying incurrent canal ; x 73. 
Figs. 12-19. Dorypleres dendyi, . . .426 
„ 12. The sponge; nat. size. 
„ 13-19. Spicules — 
Fig. 13. Somaloxea; x 51. 
„ 14-16. Somal spherasters ; x 180. 
,, 17. Ectosomal splieraster ; x 180. 
Fig. 18. Tylotoxea; x 51. (Possibly 
not proper to the sponge.) 
„ 19. Tylote end of the preceding, 
more highly magnified. 
Figs. 20-21. Craniella schmidtii, . . .39 
20. Section through an entire sponge, showing the young sponges and 
embryos within the parent ; x 22. 
21. A part of the preceding, more highly magnified, showing a planula 
penetrating the cortex ; x 51. 
