PLATE CI. 



POLYTKEMA. — TlNOPORUS. — GYPSINA. 



Diam. Page 



Figure 1. — Polytrema miniaceum, Linne\ sp., . . x 40 721 



Transparent section of the test. 



„ 2, 3.— Polytrema miniaceum, var. alba, Carter, . x 30 721 



,, 4-7. — Tinoporus baculatus (Montfort ?) Carpenter, . . 716 



Figs. 4, 5. Lateral aspect; fig. 6, peripheral aspect, . x 30 



Fig. 7. Transverse section of the test, . x 40 



„ 8. — Gypsina globulus, Reuss, sp., . . x 30 717 



,, 9-12. — Gypsina ■ vesicularis, Parker and Jones, sp., . . 718 



Figs. 9-11. Various aspects of the test, . x 30 



Fig. 12. Section, viewed by transmitted light, . x 40 



