Plate 61. 

 Showing some Features of the Internal Anatomy of 



ASTROPYGA AND MlCROPYGA. 



1, 2. Micropyga tuberculata A. Ag. 



1. Interior view, showing arrangement of alimentary canal; actinal half of test and lan- 



tern removed. The dotted lines surrounding unshaded parts are hypothetical, the 

 specimen being somewhat damaged. 



2. Lantern and perignathic girdle in position, seen from the side. 



3, 4. Astropyga radiata Gray. 



3. Interior view, showing arrangement of alimentary canal ; actinal half of test and lan- 



tern removed. 



4. Lantern and perignathic girdle in position, seen from the side. 



All figures natural size. 



