Plate V. 

 -Pourtalesia Jeffreys! Ww Thoms. 



'I'lic aniljiilncml system onlDUred. 



Fig. 25. The CMlyninal system and the surrotnuling area, p. 79. 



Fig. 26. The same I'roin the inside. 



Fig. 27. The calyciiial system and surmnnding area, in another specimen. 



Fig. 28. The same from the inside. 



Fig. 29. The tennination of the front amhiilaeniin. 



Fig. 30. Tiie articulating end of a spine, p. 24. 



Fig. 31. The corresponding tubercle. 



Pig. 32. The lower end of a spine. 



Fig. 33. A calcareous fibre rising from the collar. 



Fig. 34. A fibre with its processes, side view 



Fig. 35. Another fibre, front view. 



Fig. 36. An oar-like spine; shortened. 



