Plate X. 



Page 

 Fig. I. Halichondria tenniderma n. sp. Oxea, a i\\\\\ developed, /; developmental form, 



X 165 26 



— 2. Halichondria temiiderma n. sp. Section vertical on the surface, showing the 



skeleton, x 32 — 



— 3. Halichondria colossea n. sp. Oxea of different sizes, x 58 27 



— 4. Halichondria colossea n. sp. Dermal membrane with a few incrusted foreign 



bodies, x 58 — 



— 5. Halichondria colossea n. sjd. Canal membrane, x 58 — 



— 6 Halichondria colossea n. sp. Section vertical on the surface , from a spot where 



no projecting spicules are found; a the dermal layer of small spicules — 



— 7. Halichondria colossea n. sp. Section vertical on the surface, from a spot where 



projecting spicules are found; a the dermal layer of small spicules — 



— 8. Halichondria ? difficilis n. sp. Oxea of different sizes, a oxeum with a swelling 



in the middle, x 165 28 



— 9. Eumastia sitiens O. S. Oxea, a fully developed of different sizes, b developmen- 



tal forms, X 165 3^ 



— 10. Eumastia sitiens O. S. Transverse section of an oscular papilla, a oscular canal, 



b subdermal cavities, c the fibre lying in the partition wall, x ca. 12 _ — 



— II. Eumastia sitiens O. S. Transverse section of a pore papilla, in the middle the 



fibre with radiating branches, x ca. 12 — 



— 12. Eumastia sitiens O. vS. Wall of pore papilla, x 58 — 



