PLATE XXXIV. 



Meoma grandis, /. 1, 2. 



1. Interior of abactinal surface, to show the petals. 



2. Interior of test, to show the actinal floor. 



Spatangus purpureus, /. 3, 4. 



3. Interior of abactinal surface, to show the petals. 



4. Interior of test, to show the actinal floor. 



{All Figs, three fourths natural size.) 



