EXPLANATION OF PLATE IV 



MlCTOCYSTIS ENDOPHYLLOIDES, Eth. fil. 



Fig. I. Highly weathered example seen from above, displaying the coarse, 

 blister-like vesicular tissue, three corallites and portion of a 

 fourth ; septa weathered out may be seen on the right-hand 

 upper corallite, and a tabulate surface in the right-hand lower 

 and central corallites. x \ 



,,2. A similar specimen to that seen in Fig. 1, viewed longitudinally 

 displaying a calice and portion of a visceral chamber with 

 tabulae, etc. x \. 



,, 3. Portion of a visceral chamber surrounded by cysts ; in the former 

 septal lamella) and close-set tabulre. 



,, 4. The same visceral chamber seen in Fig. 3, but viewed at a some- 

 what different oblique angle. 



