EXPLANATION OF PLATE XXI. 
Fig. 1.-_Echinaster eridanella, Miller and Troschel. Photo- 
graph of a specimen with four rays from Mauritius. 
Abactinal view. Natural size. 
Fig. 2.—Echinaster eridanella, Miller and Troschel. | Photo- 
graph of a specimen with seven rays from Bowen. 
Queensland. Abactinal view. Natural size. 
