PLATE 76. 
Hyalonema (Prionema) agujanum tenuis LeNnpENrELD. 
Figs. 1-7, 11, 12, 15-36 —form A. 
Figs. 8-10, 18, 14 —form B. 
1.— The centrum and one ray of a microhexactine of form A; magnified 2000; u. v. phot. Zeiss, q. 
monochr. 1.7, q. oc. 10. 
2, 3.— Micramphidises of form A; magnified 500: 
2, phot. Zeiss, H. I. apochr. 2, compens. oc. 6; 
3, phot. Zeiss, apochr. 4, compens. oc. 12. 
4-6.— Portions of transverse sections of a Palythoa polyp attached to the stalk of a ape of form A; 
magnified 100; phot. Zeiss, apochr. 16, compens. oc. 6. 
7.— Axial, longitudinal section through the upper part of the stalk with Palythoa attached, and the 
lower| part of the body of form A; magnified 6; phot. Zeiss, planar 50 mm. 
8-14.— Acanthophores from the sponge; magnified 200; phot. Zeiss, apochr. 8, compens. oe. 6: 
8, a small regular tetractine of form B; 
9, a large regular pentactine of form B; 
10, a large irregular tetractine of form B; 
11, 12, small regular tetractines of form A; 
13, a large regular tetractine of form B; 
14, a large diactine of form B. 
15-32.— Acanthophores and other sponge-spicules formed in a Palythoa polyp on the stalk of a speci- 
men of form A; magnified 200; phot. Zeiss, apochr. 8, compens. oc. 6: 
15, 16, short diactines, much more spiny at the ends than in the middle; 
17-20, short and stout rod-shaped spicules; uniformly spined throughout; 
21, 22, small stout triactines; uniformly spined throughout; 
23-30, small stout tetractines, uniformly spied throughout; 
31, a small only terminally spined tylostyle; 
32, a minute pentactine. 
33.— The tip of an anchor-tooth of a large serrated mesamphidise of form A; magnified 2000; u. v. 
phot. Zeiss, q. monochr. 1.7, q. oc. 10. 
34.— Transverse section through the upper part of a Palythoa polyp attached to the stalk of a specimen 
of form A; magnified 30; phot. Zeiss, planar 20 mm. 
35, 36.— The end-part of an anchor-tooth of a large mesamphidise of form A; magnified 2000; u. v. 
phot. Zeiss, q. monochr. 1.7, q. oc. 10: 
35, focussed higher; 36, focussed lower. 
