Plate XI. 



Edrioaster bigsbyi. Specimen B, from drawings made in 1899 by Mr. Gilbert C. 

 Chubb. 



Fig. 1. Adoral face, with the posterior interradius towards the observer. 

 Cover-plates are preserved in all the rays, but are pressed into the grooves, 

 x 2 diam. 



Fig. 2. The adcentral region of the posterior interradius, showing the 

 hydropore. x 10 diam. 



[1914 125] 



