PLATE XIX. 



Concavum-beds. 

 Figs. 1 — 4. — Hyperlioceras discoidetjm (Quenstedt). 



Fig. 1. — Side view of a large adult specimen (var. )3). Bradford Abbas, 

 Dorset. My Collection. (Page 98.) 



Fig. 2. — Front view of the same specimen. 



Fig. 3. — Side view of another form (var. a). Bradford Abbas, Dorset. My 

 Collection. 



Fig. 4. — Outline of the front view of the same specimen, showing triangular 

 aperture, and concave inner margin with the upper edge overhanging the lower. 



Figs. 5, 6. — Hyperlioceras subdiscoideum, 8. Buchman. 



Fig. 5. — Side view of a specimen with all its test well-preserved. (At the top 

 left-hand corner the carina and ventral area have been broken away ; but, as 

 depicted in the figure, it might be thought the carina were hollow, which is not 

 the case.) Bradford Abbas, Dorset. My Collection. (Page 100.) 



Fig. 6. — Sectional view through the same specimen, showing the umbilicus 

 contracted by the last turn. 



