PLATE LII. 
Sauzei-zone. 
Figs. 1 — 3. — DoESETENSiA, sp. (A). 
Fig. 1. — Side view of a specimen without test. Frogden Quarry. Oborne. My Collection. 
(Page 304.) 
Fig. 2. — Front view. 
Fig. 3. — Outline of ventral area, enlarged. (Dr. Haug suggests that this is a young specimen of 
his " Sarpoceras alsaticim ;" but, having compared it with a plaster cast of his species, I do not feel 
sufficient certainty to append that name.) (Page 304.) 
Figs. 4 — 7. — DoESETENsiA, sp. (B). 
Fig. 4. — Side view of a specimen with test, showing straight ribs. Frogden Quarry. Oborne. 
My Collection. (Page 304.) 
Fig. 5. — Front view. 
Fig. 6. — Outline of ventral area, enlarged. 
Fig. 7. — Suture-line. The accessory lobe in the superior lateral saddle and the first auxiliary lobe 
are decidedly exaggerated. (This specimen has much resemblance to the young of some species of 
WitcTiellia, but it is distinguished from them by its very straight ribs.) 
Sumphriesianum-zone, 
Figs. 8 — 24. — 'DoESETENSiA Edouabdiana {d'Orhigny). 
Fig. 8. — Side view of an evolute, coarse-ribbed example (a). Sherborne. From my father's 
Collection. (Page 304.) 
Fig. 9. — Front view of the same specimen. 
Fig. 10. — Suture-lines of the same specimen. 
Fig. 11. — Side view of an evolute, fine-ribbed specimen (aa). Milborne Wick, Somerset. From 
my father's Collection. 
Fig. 12. — Front view of the same shell. 
Fig. 13. — Outline of the ventral area, enlarged. 
Fig. 14. — Inner whorls, enlarged, showing the ovoid protoconch, and the development of the ribs 
from small knobs. (See PI. XLIX, fig. 4.) 
Fig. 15. — Side view of a specimen with the mouth-border apparently complete (/3). Sherborne. 
From my father's Collection. 
Fig. 16. — View of the same specimen from the top, showing the ventral lappet of the mouth. 
Fig. 17. — Outline of the ventral area, enlarged. 
Fig. 18. — Side view of a somewhat involute form, which agrees with d'Orbigny's figure more 
exactly than any of the other specimens (y). Frogden Quarry, Oborne. My Collection. 
Fig. 19. — Front view. 
Fig. 20. — Outline of the ventral area, enlarged. 
Fig. 21. — Side view of a more involute form, with obsolescent ribs (S). Frogden Quarry, Oborne. 
My Collection. 
Fig. 22. — Front view of the same shell, showing sharper ventral area. 
Fig. 23.^ — Suture-line of the same specimen. 
Fig. 24. — Outline of the ventral area enlarged, showing loss of ventral furrows. (Omitting figs. 
11 — 13, the specimens of Dorsetensia Edouardiana are arranged to illustrate every step in the change 
from evolute, well-ribbed, suleate-carinate whorls to involute, nearly smooth, acutely-carinate whorls. 
All the specimens have more or less test preserved.) 
Figs. 25 — 27. — DoESETENsiA puLCHRA, S. Buchnan. 
Fig. 25. — Side view of specimen showing the ribs degenerating to striis. It will be noticed that 
on the outer whorl the test is striate, but the core has very faint though rather broad ribs. Frogden 
Quarry, Oborne. My Collection. Unique example. (Page 306.) 
Fig. 26. — Back view, showing depressed areas each side of a fairly prominent carina. 
Fig. 27. — Suture-lines, showiug an array of small auxiliary lobes. (This specimen seems to be the 
link between Lycettia Edouardiana (y), and Lycettia Romani, Oppel sp.) 
