PLATE IX. 



Fig. I. Echinoimiricea collaris n. sp. Natural size. 



Fig. 2. Echinomuricea spinifera n. sp. Natural size. 



Fig. 3. Thesea placoderina n. sp. Natural size. 



Fig. 4. Thesea flexilis n. sp. Natural size. 



Fig. 5. Thesea sanguinea n. sp. Natural size. 



