PLATE XXXIII 

 MICHELINIA CON VEX A D'ORBIGNY (PAGE 432) 



FIGURE 1. Development of a group of corallites from initial conical 

 cell to corallum with nineteen calices. The figure represents parallel 

 horizontal sections through the corallum ; showing the number and form 

 of the calices, their order of development, and the modifications taking 

 place during growth. The parent cell is marked A ; first series of calices, 

 1, 2, 8, etc. ; first series of intermural buds, 1', 2', 3', etc. ; peripheral 

 series, 1", 2", 3", etc. Notation corresponds with that of preceding plate. 

 Natural size. 



