PLATE I. 



Fig. I. Palccacis cuneiformis. A series of individuals showing 

 alternate bilateral budding. X 2. 



Fie. 2. Palceacis obhtsa. View of the calices of a mature 

 corallum. The lowermost in the figure is the 

 oldest, and was followed successively by the upper- 

 most, the one at the left, and the one at the 

 right. X 2. 



Fig. 3. Palcracis ohtusa. Transverse section showing canals 

 (white), radiating fibres, and infiltration of silica and 

 pyrite (black). X 8. 



Fig. 4. Microcyathiis deprcssiis. Transverse section showing 

 skeletal structure, openings of canals into interior 

 cavity, and calicular ridges. X 8. 



Fig. 5. Calostylis dcnticulata. A corallum which shows the 

 pinnate arrangement of septa. Nat. size." 



Fig. 5a. A detail of the same specimen. X 2. 



Fig. 6. Calostylis denticulata. Tracing of a microphotograph 

 showing quadriseptate arrangement of septa in the 

 upper (cardinal) quadrants. X H- 



Fig. 7. Heterophyllia cf. sedgzvicki. View of a calyx which 

 shows an imperfect quadriseptate grouping of the 

 septa. X 4- 



Fig. 8. Heterophyllia cf. sedgzvicki. Retouched photograph of 

 a transverse section showing a complete quadrisep- 

 tate group in the lower right-hand quadrant. X /• 



Fig. 9. Hexaphyllia cf. mccoyi. Transverse section showing- 

 bilateral symmetry. X 8. 



Fig. 10. Pachyphyllum zvoodmani. View of attachment surface 

 of colony showing a tracing of the protocorallite with 

 four septa. X 5- 



