404 



Annals New York Academy of Sciences 



Figures 7-8. Stauroneis acuta W.Sm. In figure 7 is shown the extension of the cham- 

 bers along the line of the striae, figure 8 the inner membrane with tine pores in triangular 

 tesselation and the iiroad slit along the line of the striae. Figure 7, X5000. Figure 8, 

 X 40,000. 



Figures 9-10. Stauroneis amphioxys Greg. Figure 9, X2500. Figure 10, X40,000. 



Figures 11-12. Stauroneis salina W.Sm. Figure 11, X2000. Figure 12, X40,000. 



