xc INFERIOR OOLITE AMMONITES. 



/3. Anguliradiatse. 



19. Ludwigella rugosa, 8. Buchuan. Suppl., Plate XX, figs. -'54 — 36. 



Distinction. — From LudJ. impolita, more closely set, less conspicuous costse, 

 which show an angulate radial line. 



Locality and Stratum. — Dorset : Stoke Knap, in the Building Stone. 

 Date of Existence. — Bradfordensis hemera, perhaps. 



Series F — Ludwigella*: carinas. 



A fairly distinctly separated carina and coarser ornament distinguish these species 

 from Series E. They represent, however, two groups ; one being somewhat thick- 

 whorled with small umbilicus, the other more compressed, but with larger umbilicus. 



20. Ludwigella nodata, 8. Bud-man. Suppl., Plate XIX, figs. 34 — 30. 



Locality and Stratum. — Dorset : Stoke Knap, in the Building Stone. 

 Date of Existence. — Bradfordensis hemera, presumably. 



21. Ludwigella carinata, 8. Buchuan. Suppl., Plate XIX, figs. 40—42. 



Distinction. — From Lvdl. nodata, a wider umbilicus, a more compressed whorl, 

 and less conspicuous ornamei it. 



Locality and Stratum. — Dorset: Stoke Knap, in the Building Stone (rather 

 common) — more than one specimen has the exact layer recorded ; it is 6 ; Bradford 

 Abbas [marl of Paving Bed?] (Monk Collection). 



Date of Existence- -Bradfordensis hemera. 



Scries G — Ludwigella subrecta. 

 Close-set and nearly straight ribs are the distinctions in this case. 



22. Ludwigella opaca, S. Buchnan. Suppl., Plate XIX, figs. 1 ( .> — 21. 



Description. — Subplatysubleptogyral, sublatumbilicate ; subparvicostate. 



Localities and Strata. — The figured specimen is from my father's collection. 

 It is mostly of a blackish colour from a dark calcareous matrix. I do not know the 

 locality, unless it be Yorkshire; but the matrix is so distinctive that it should be 

 recognisable by those acquainted with the strata. Dorset: Burton Bradstock, from 



