224 



Pyrosoma Spinosum, Herdman 



EXPLANATION OF PLATES 



Plate I. 

 Pyrosoma spinosum. x|. From a photograph. 



Fig. 

 Fig. 



a.m. 

 an., 

 a.s., 

 d.g. 

 en., 

 Ian. 

 hi., 



Plate II. 



1. — Pyrosoma spinosum : lateral view of zooid. 



2.— Pyrosoma spinosum : oral aperture of zooid, from within. 



., atrial muscle. 



anus. 



anal sphincter. 

 , dorsal ganglion, 

 endostyle. 

 , languets. 

 luminous organ. 



m., oral aperture. 



o.s., oral sphincter. 



ov., ovary. 



st., stolon. 



s., stomach. 



t.m., transverse muscle. 



v.t., ventral tentacle. 



On page 



ERRATA. 



24, for Plate I read Plate VI. 

 for Plate II read Plate VII. 



