PLATE IV. 



Fig. I. Plexaura aggregate/, n. sp. Group of 5 spicules, a, b, c, d, e. X 112. 



Fig. 2. Plexaura attenuata n. sp. Group of 3 spicules, a, b and c. X 112. 



Fig. 3. Plexaura recta n. sp. Group of 3 spicules, a, b and c. x 112. 



Fig. 4. Plexaura platystoma n. sp. Group of 3 spicules, a, b and c. X 112. 



Fig. 5. Plexaura pinnata n. sp. Group of 4 spicules, tf, , , d. X 112. 



Fig. 6. Plexaura flava n. sp. Group of 4 spicules, , , c, d. X 112. 



Fig. 7. Euplexaura rubra n. sp. Group of 3 spicules, , and c. ; 112. 



Fig. 8. Euplexaura mollis n. sp. Group of 4 spicules, , , c and */. X 112. 



Fig. 9. Euplexaura reticulata n. sp. Group of 4 spicules, a, b, c, d. ) ; 1 1 2. 



Fig. 10. Hicksonella princeps n. sp. Group of 6 spicules; , , c, d, e and . X "2. 



a and * represent one of the two general types, and the rest the other, or tuberculate type. 



