Plate 63. 

 Perignathic Girdles, Lanterns, and Stewart's Organs of Echinothurids, in natural posi- 

 tion, seen from the side. 



1. Sperosoma obscurum A. Ag. and CI. 



2. Asthenosoma Ijimai Yosh. 



3. Phormosoma bursarium A. Ag. 



4. Echinosoma hispidum Mortens. 



All figures considerably enlarged. 



