152 Mr. Forbes on the Radiata of the Eastern Mediterranean. 



The Mediterranean specimens are somewhat smaller than the British, but 

 do not appear to differ in any essential point. O. tricolor, pentagona, Ferus- 

 saci, Cuvieri, and quinquemaculata of Delle Chiaje seem to be all varieties of 

 this very variable species. 



Common in the ^Egean, and on the coast of Asia Minor, among rocks near 

 sea-mark ; not frequent in deep water. 



EXPLANATION OF THE PLATES. 

 Tab. XIII. 



Fig. 1 . Pectinura vestita, of the natural size. 



2. Diagram of the upper surface of the body. 



3. Diagram of the lower surface of the body. 



4. Ovarial plates. 



5. Superior arm-scales. 



6. Inferior arm-scales. 



7. Lateral arm-scales, with spines. 



8. Ophiura abyssicola, of the natural size. 



9. Upper arm-scales and pectinated scales of the base of the arm. 



10. Lower arm-scales. 



11. Diagram of the upper surface of the body. 



12. Diagram of the lower surface of the body. 



13. Lateral arm-scales, with spines. 



14. Ovarial plate. 



15. Ophiomyxa lubrica', upper surface of the disc. 



16. Under side of ray. 



17. Upper side of ray. 



18. Ovarial plates and mouth-defence. 



19. A mouth-spine. 



20. A ray-spine. 



21. Lateral view of ray-spines. 



22. The disc-shields and their articulations. 



