PLATE I. 



Fig. 



1. Biflmtra delicatula (recent). 



2. (fossil), p. 7-2. 



3. Flustra (?) dubia, p. 131. 



4. Biflustra delicatula, p. 72. 



a. Posterior aspect of lamina. 

 Ij. Horizontal section. 

 c. Longitudinal section. 



). Hippothoa pqtayonira, p. :24. 

 b'. Scrupocellaria scruposa (?) p. 19. 



7. Hippothfa dentata, p. :J(i, 



. Magnified '25 diameters. 

 5. Magnified 50 diameters. 



5. Crisis denticulata, p. 93. 



