I 



PLATE 58. 



Hyalonema (Prionema) azuerone Lendenfeld. 

 Figures 1-22. 



1. — Part of a section through the choanosome, showing a canaJ-wall; magnified 100; phot. Zeiss, 



apochr. 16, compens. oc. 6: 



a, canal-wall; b, canalar pinules; c, microhexactines; d, micramphidiscs. 



2. — Part of a section through the choanosome, showing a region particularly rich in small macram- 



phidiscs; magnified 100; phot. Zeiss, apochr. 16, compens. oc. 6. 



3. — Section vertical to the surface through the superficial part of the sponge; magenta; magnified 30; 



phot. Zeiss, planar 20 mm.: 



a, outer surface with jiinule-fur; b, group of fiagellate chambers; c, wall of a canal. 



4. — Surface-view of a pore-sieve on the lower side of the sponge; magnified 20; phot. Zeiss, planar 



20 mm. 



5-9. — Parts of anchor-teeth of macramphidiscs; magnified 2000; u. v. phot. Zeiss, q. monochr. 1.7, 

 q. oc. 10: 



5, a portion of the middle-part of a tooth; 



6, 7, the end-part of a tooth; 



6, focussed lower; 7, focussed higher; 



8, the end-part of a tooth; 



9, portion of the basal part of a tooth. 



10. — Part of the superficial pinule-fur, from a section vertical to the surface; magnified 100; phot. 



Zeiss, apochr. 16, compens. oc. 6. 



11. — Surface-view of a portion of the superficial pinule-fiu on the lower side of the sponge; magnified 20; 



phot. Zeiss, planar 20 mm. 



12. — A slender-shafted micramphidisc; magnified 2000; u. v. phot. Zeiss, q. monochi". 1.7, q. oc. 10. 



13. — A medium mesamphidisc; magnified 2000; u. v. phot. Zeiss, q. monochr. 1.7, q. oc. 10. 



14. 15. — Apical views of the crosses formed by the lateral rays of the superficial pinules; magnified 300; 



phot. Zeiss, apochr. 8, compens. oc. 12. 

 16-22. — -Side-views of pinules; magnified 300; phot. Zeiss, apochr. 8, compens. oc. 12; 



16, 19, canalar pinules; 



17, 18, 20-22, superficial pinules. 



