PLATE VI". 



Hipponoe esculenta, /. 1-3. 



1. Seen from actinal side, f nat. size. 



2. Same seen from abactinal pole. 



3. Young, from abactinal pole, nat. size. 



Echinus norvegicus, / i. 



4. Seen from abactinal pole, nat. size (from Cape Wrath). 



Diadema setosum, /. 5. 



5. Seen from abactinal pole, | nat. size. 



Echinus gracilis, / 6. 

 G. Seen in profile, | nat. size. 



