Plate 63. 

 Perignatliic Girdles, LanternSj and Stewart's Organs of Echinothurids, in natural posi- 

 tion, seen from the side, 



1. Sperosoma obscurum A. Ag. and CI. 



2. Astbenosoma Ijimai Yosh. 



3. Pbormosoraa bursarium A. Ag. 



4. Ecbinosoma bispidum Mortens. 



All figures considerably enlarged. 



