PLATE XXXVI. 
Azorica jpfeifferge, 
Figure 1. The sponge ; nat. size. 
„ 2-20. Spicules — 
Figs. 2, 3. Oxeas; x 95. 
„ 4-13. Various stages in the growth 
of the desma j x 95 (except fig. 9, 
which is X 200). 
Figs. 14-19. Various forms of the fully 
grown desma; x 95. 
„ 20. Two desmas in zygosis; 
X 200. 
21. Part of section through the choanosome, showing the general appear- 
ance of the tissue ; x 180. 
22. Section at right angles to the surface, showing fusiform cells directed 
at right angles to the external epithelium ; x 300. 
23. ' Part of a section through the choanosome ; x 360. 
24. Isolated mesodermal cells ; x 430. 
25. Section through the choanosome, showing the general characters of the 
chamber-system ; x 360. 
26. Similar to the preceding, but more highly magnified ; x 430. 
27. Longitudinal section through one of the water canals ; x 240. 
28. Section at right angles to the surface, showing the arrangement of the 
subdermal cavities ; x 34. 
29. Part of a similar section taken from the oscular side of the sponge; 
X 180. 
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