PLATE IX. 



Palasterina stellata (page 76). 



Figure la. The specimen natural size. 

 " \h. The same enlarged. 



Palasterina rugosa (page 77). 



Figure 2a. Dorsal view of a specimen from the Hudson River group, Anticosti. 

 " 26. Fragment of another individual. 

 " 2c. One of the plates enlarged. 



Petraster rigidus (page 80). 



Figure 3a. Ventral view of an imperfect specimen. 

 Fig. 3a appears to be the dorsal side of an individual of this species with the plates 

 along the centre of the rays removed. 



