EXPLANATION OF PLATE XXI. 



Fig. L — Echinuster eridanella, 3iuller and Troschel. Photo- 

 graph of a specimen with four rays from Mauritius. 

 Abactinal view. Natural size. 



Fig. 2. — Echinaster eridanella, Miiller and Troschel. Photo- 

 graph of a specimen with seven rays from Bowen, 

 Queensland. Abactinal view. Natural size. 



