HUGHES : INGLEBOROUGH. 
307 
Fig. 1. — P. gigantea, rotund form, from the Lower 
Gigantea Zone, below Farrer's Shooting Box, 
Ingleborough. 
Fig. 2. — P. gigantea, rotund and strongly cor- 
rugated form, from the top of the Mountain 
Limestone, Plovrigg, Crosby Ravensworth. 
Fig. 3. — P. costata, from the Lower Gigantea Zone, 
Hull Pot, Horton-in-Ribblesdale. 
Description of Map, Plate XXIX. 
The map is drawn on the scale of nearly 2,000 feet to the 
inch, and is intended to show the outcrops of the Grit on 
the summit ; of the Massive Sandstone under the Main 
Limestone ; and all the limestones of the Yoredale Series 
down to the Great Scar or Mountain Limestone. 
The principal streams and other features referred to in the 
paper are shown. 
The line of section across Simon Fell, on the same scale as 
the map, is indicated by a dotted line. 
The letter A refers to the Black Shaley Limestone (the Lower 
Zone of Producta gigantea) on top of the Great Scar or 
Mountain Limestone. 
B is the Black Marble above and separated by a shale from 
the Lower Gigantea Zone. No line is drawn between 
A and B and the dividing shale is not shown on the 
map. 
C is the Hardrow Limestone. 
D the Simonside Limestone. 
E the Middle Limestone. 
F the "Lnpure Productal Limestone." 
G the Main or Upper Scar Limestone, including the Upper 
Gigantea Zone. 
XXXIX. 
