PLATE L. 



PAGE 



Poliopogon amadou, Wyville Thomsou, . . .254 



Fig. 1. Vertical section through the marginal portion (combination figure) ; x 25. 



Fig. 2. Vertical longitudinal section of a very young specimen (combination 

 figure) ; x 20. 



Fig. 3. Uncinatum-like oxydiact ; x 50. 



Fig. 4. Superior end of a marginal spicule ; x 300. 



Fig. 5. Autodermal pentact pinulus ; x 300. 



Fig. 6. Oxyhexact with straight echinated x'ays ; x 300. 



Fig. 7. Inferior end of an anchor-like spicule of the basal tuft ; x 50. 



Figs. 8-12. Large, middle-sized, and small amphidiscs ; x 300. 



