518 
PEOFESSOE OWEN’S DESCEIPTION OF THE CAYEEN OF 
Vicomte de Lastic St. Jal) is of an oblong form (fig. 2), about 20 feet in width, and from 
8 to 12 feet in height; the cavern (fig. 4) widens a little beyond the entry, expanding 
to a breadth of about 50 feet two-thirds of the way towards the opposite end : the length 
of the cavern is between 60 and 70 feet; it has a pretty regular domed roof (fig. 3), and 
from the lowest part of the present excavated floor to the top is from 15 to 20 feet. 
Fig. 2. 
The roof is evenly coated by a thin layer of stalactite, which now shows a few, and 
those but small, dependent processes ; a larger columnar mass which reached to the floor 
near the back of the cave (fig. 1, to), had been removed before my visit (January 23rd, 
1864). The original level of the peripheral part of the stalagmitic floor, was shown, 
at that date, by the adhesion to the wall of a portion projecting like a shelf, fig. 3, s, s, 
from 1 foot to 2 \ feet in breadth, and averaging 1 foot in thickness, along about two- 
thirds of the circumference of the cavern. Upon this shelf the stalactitic coating of the 
cavern-wall is continued ; the shelf of stalagmite slopes slightly from the wall to its 
broken margin. The breccia exposed by the breaking up of the stalagmitic floor slopes 
irregularly towards the middle of the fore part of the cavern, where the excavations 
have been carried deepest. Blocks of breccia covered by the stalagmite had been succes- 
