﻿PLATE XL 



Figs. 1 — 6. Arch^ediscus Karreri, Brady. (Page 142.) 



Figs. 1 a, 2. Lateral aspect. Magnified 38 diameters. 

 Fig. 1 b. Periphero-lateral aspect. X 38 diam. 



Fig. 3*. Horizontal section. That the shell-wall has no appreciable thickening 

 on the median plane is shown by the outer circlets. X 38 diam. 



Fig. 4. Transverse section, showing the thickening of the walls, especially 

 near the centre, and their extensive tubulation. X 38 diam. 



Fig. 5. Lower portion of same section further enlarged, with indications of 

 two distinct sorts of tubuli, and of a primary shell-wall, distinct from the 

 supplementary thickening. X 230 diam. 



Fig. 6. Part of a transverse section, showing the successive layers formed by 

 the prolongation of the crescentiform edges of the tubulated shelly investment 

 over the lateral surfaces of the test. X 230 diam. 



Fig. 7. Amphistegina minuta, nov. (Page 146.) 



a lateral, b periphero-lateral aspect. X 50 diam. 



Figs. 8 — 11. Nummulin a pristina, Brady. (Page 149.) 



Fig. 8 a lateral, b periphero-lateral aspect. X 50 diam. 



Fig. 9. Specimen split on the median plane, showing interior arrangement and 

 septation. X 50 diam. 



Fig. 10. Transverse section, showing the somewhat large primordial chamber, 

 the investing character of the alar lobes of the chambers of the spire, and the 

 resulting lamination of the test ; also the general tubulation of the shell, and at 

 the lower extremity some indication of the marginal cord. X 100 diam. 



Fig. 11. Small portion of a horizontal section more highly magnified, demon- 

 strating the existence of a canal-system in the septa and peripheral region. 

 X 200 diam. 



* In the lettering of the Plate the 3 has been accidentally omitted ; the centre figure on the top row 

 is the one alluded to. 



