PLATE I. 



Fig. I. Plexaura aggregata n. sp. Natural size, i a, part of branch X 5- 

 Fig. 2. Plexaura attenuata n. sp. Natural size. 2 a, part of branch X $ 

 Fig. 3. Plexaura pinnata n. sp. Natural size. 3 a, part of branch X 5- 



