Plate 1. 

 Pourtalesia Jeffreys! Wyv. Tiioms. 



'I'lie ainbuincral system coloured. 



Fia;. 1. Tlie skeleton, denuded; dorsal aspect. 



Fig-. 2. The same, ventral aspect. 



Fig. 3. The same, side view. 



Fi°:. 4. The periproct and the anal membrane. 



F'ig. 5. A pedicellar peripodium and tubercles. 



Fig. 6. A lateral plate of an ambulacrum, with a pedicellar pore marked 



Fig. 7. The same from the inside. 



Fig. 8. The sub-labial area of another specimen. 



