84 HISTORICAL AND STRATIGRAPHICAL GALLERY. 
British 
Stratigraphi- 
cal collection. 
Collection of Brachiopods, the types of Sowerby's "Mineral 
Conchology," and lastly, but not least in interest, specimens 
from the collection of Sir Hans Sloane, which was the nucleus 
of the whole Museum. 
In the wall-cases on the west side of this gallery is exhibited 
a stratigraphical collection, showing a series of rock-specimens 
Fig. 56. — An Ammonite, 
FROM THE Oolite. 
Fig. 55.— a Turrilite, 
from the Chalk. 
Fig. 57.— a Trilobite, from the Lower Cambrian of Shropshire. 
often with their included fossil remains, representing the 
various geological formations of the British Isles, arranged in 
the order of their sequence in time, commencing near the 
entrance door with the most recent, and gradually passing 
down to the most ancient fossil-bearing strata. Along the top 
of the case is displayed a running section of all the water- formed 
