Plate i. 

 Pourtalesia Jeffreysi Wyv. Tiioms. 



The ombulacral system coloured. 



Fig. 1. The skeleton, deuuded ; dorsal aspect. 



Fig. 2. The same, ventral aspect. 



Fig. 3. The same, side view. 



Fig. 4. The periproct and the anal membrane. 



Fig. 5. A pedicellar peripodiura and tubercles. 



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



Fig. 7. The same from the inside. 



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



