io6 



TH. MORTENSEN, 



(Schwed. Siidpolar-Exp 



Plate I. 



Ctenocidaris speciosa Mrtsn. Abactinal side. Most of the radioles of this specimen are 

 wholly invested with the colonies of a Bryozoon of the genus Alcyonidium. Nat. size. 



Plate II. 



Ctenocidaris speciosa Mrtsn. Actinal side. Most of the radioles are closely set with a bi- 

 valve Mollusc of the genus Limopsis. Nat. size. 



Plate III. 



Fig. i. Ctenocidaris speciosa Mrtsn. Abactinal side. 



» 2. » » » Actinal » 



» 3. Austrocidaris spinulosa Mrtsn. Actinal side. 



> 4. » » Abactinal » 



» 5. » » » Young specimen. Side view. 



» 6. canaliculata (A. Ac) Abactinal side. 



» 7. » » » Actinal » 



» 8. » » » Side view. 



All the figures natural size. 



Plate IV. 



Fig. r. Ctenocidaris speciosa Mrtsn. Side view. 



» 2. » » » Abactinal side. 



» 3. » » » Actinal » 



» 4. Austrocidaris canaliculata (A. Ac). Side view. 



» 5. » » » Female specimen. Abactinal side. 



» 6. » » » Male » » » 



» 7. » » » Abactinal side. 



» 8. » » » Side view. 



» 9. » » » Female specimen. Abactinal side. 



» 10. » » » » » > » 



» 11. » » » Actinal side. 



The figures 4, 8, and 1 1 slightly magnified, the rest natural size. 



