PLATE XCIII. 



Concavum-zone. 

 Figs. 1 — 6. — Sonninia renovata, 8. Buckman. 



Fig. 1. — Side view of a specimen with most of the test present, but in a some- 

 what inferior condition. Reduced to two-thirds natural size. (It shows a second 

 spinous stage following a costate stage, which is preceded by an irregular, and 

 that by a regular spinous stage. It came from Bradford Abbas, and by its colour 

 and condition evidently from the very top of the Concavum-zone immediately 

 under the " Irony bed," — the bed No. 4 of the section in page 5.) My Collec- 

 tion. (Page 433.) 



Fig. 2. — Front view of the same shell in outline. Natural size. 



Fig. 3. — Part of the suture-line of the same shell, showing the very long lobes. 



Fig. 4. — Side view of an immature shell before the return to knobs has 

 commenced. Natural size. Bradford Abbas. From the Collection formed by 

 Mr. Darell Stephens, F.G.S. Now in my cabinet. 



Fig. 5. — Outline of the whorl-section and periphery. 



Fig. 6. — Part of the suture-line showing the long lobes. 



Fig. 7. — Sonninia crassispinata, S. Buckman. 



Fig. 7. — Portions of two septal outlines of the specimen of Sonn. crassispinata 

 figured in PI. LVII. This figure is drawn from a photograph, and is the result 

 of a fresh study of the suture-lines for comparison with those of Sonn. locuples )3, 

 PI. XCII, fig. 4. To the point of the siphonal lobe the radius is 71 mm. It will 

 be noticed that the superior lateral saddle is incomplete — the outline could not be 

 followed. (Page 425.) 



