EXPLANATIOX OF ri.AlK VII. 



Spungoplivlluiu lialvsitoides, Et/i. til- 

 Fig. 1. Weathered surface of portiuu of a curalluni. Witli the aid of a 

 pocket lens, and iu some of the corallites eveu without, the 

 Hnctuatiiig walls of the latter, reseiiihling the structure of 

 tlie corallites in //(f/_//.s)7e.s, are distinctly visible. 



2. Transverse section prepared for the microscope exhibiting the 

 same features as in Fig. 1, especially at the left hand corner 

 of the section. Also the peri])heral vesicular /one of each 

 corallite, the non-septate inteiniediate aiea, and the central 

 vesicular space — x 8 diam. 



o. Similar longitudinal section. It will be iu)ticed tlial wliat 

 should be the intermediate septal aiea /one is I'eally a 

 tabulate area supported without and within by convex 

 surfaces of the peripheral and central vesicles resj)ectively 

 — X 8 diam. 



