FROM THE GAULT. 33 



The epitlieca is waved and well developed. The spaces between the larger costse are 

 more or less angular. 

 The peduncle is large. 

 Locality. Gault, Folkestone. In the British Museum. 



Variety 2 (PI. XIII, figs. 3, 4). — The corallum is as large as that of variety 1, but it 

 is more conical. 



The costse are less pronounced, and the septa, which are more granular than those of 

 variety 1, arise from the intercostal spaces. The costal ends are very elegant in shape, 

 and form a margin of rather sharp curves, side by side. 



Locality. Gault, Folkestone. In the British Museum. 



Variety 8 (PL XII, figs. 1, 8, 4 ; and PL XIII, fig. 13).— The corallum is rather flat, 

 but hemispherical. 



The septa are not exsert, and they arise from the costal ends. 



The costse are equal ; none are more prominent than others. They are all rather 

 broad, flat, and beautifully ornamented with diverging curved lines. Their free ends are 

 equal and carved. 



Locality. Gault, Folkestone. In the Collection of the Rev. T. Wiltshire, F.G.S. 



Variety 4. — The corallum and costse are like Variety 3, but the septa arise from the 

 intercostal spaces. 



Locality. Gault, Folkestone. In the Collection of the Rev. T. Wiltshire, F.G.S. 



Variety 5 (PI. XII, fig. 2). — The corallum is rather more conical inferiorly than in 

 Varieties 3 and 4. 



The septa are exsert, and project slightly beyond the costal margin. 

 The costse are all rudimentary. 



The epitheca is well developed, and reaches up to the septa. 

 Locality. Gault, Folkestone. 



The forms may be distinguished as follows : 



( The type. 

 With more or less ridged costse . . . ■< Variety 1. 



C „ 2. 



With nearly equal flat costse 

 Costse rudimentary 



Septa arising from the costal ends 

 Septa arising from the intercostal spaces 



f Variety 3. 



I ,. 4. 

 Variety 5. 



( The type. 

 \ Variety 1 . 

 ( „ 3. 

 f Variety 2. 

 I „ 4. 



