PLATE X. 



Fig. 1. — Carbonicola aquilina. A large form from the roof of the Moss Coal, 

 Longton. Collection of Mr. John Ward, F.G.S. (Page 69.) 



Figs. 2 — 6 — Carbonicola aquilina. A series from the roof of the Moss (or 

 Bastling) Coal. Lane End Colliery, Fenton. My Collection. (Page 69.) 



Figs. 7 — 17. — Carbonicola aquilina. A series to show variability in form, from 

 the roof of the Hard Mine Coal, Adderley Green. My Collection. (Page 69.) 



Fig. 18. — Carbonicola aquilina. From a plaster-of -Paris cast. The original 

 passed through my hands in transit from Mr. George Wild to Professor Amalizky, 

 of Warsaw. From the Stubb's Mine, Bardsley. Cast in my Collection. (Page 69.) 



Figs. 19 — 42. — Carbonicola aquilina. A series of casts from the roof of the 

 Hard Mine Coal, Adderley Green, to show stages of growth and the variation in 

 form of even young examples, the smallest forms resembling the TJnio phaseolus 

 of Sowerby. My Collection. (Page 69.) 



Figs. 19 a, 20 a, 21 a. — Figs. 19, 20, and 21 viewed from above, showing casts of 

 the hinge-line and umbones. The anterior adductor scars and those from the 

 accessory pedal muscles above and posterior to them are well seen, also the 

 sinuous line indicating the position of the hinge-teeth. (Page 69.) 



