250 
THE MIDDLE LIAS OF NORTHAMPTONSHIRE. 
Dr. Klein’s illustration, 
showing rings. Magnified 
about 700 diameters. 
Dr. Klein. 
Dr. Swayne. 
For further details see British Medical Journal of March 
21st, page 589. 
THE MIDDLE LIAS OF NORTHAMPTONSHIRE. 
BY BEEBY THOMPSON, F.G.S., F.C.S. 
PART I. 
(Continued from page 213.) 
Description of Beds in the “ Spinatus” Zone. 
I have found it more difficult to correlate the beds of the 
“ Spinatus ” Zone than those of the “ MargaritatusJ because 
there are very few sections in which the beds just below the 
rock-bed can be seen, and these few are long distances apart. 
It is possible that the rock-bed (“ B ”) is the sole representative 
of the “ Spinatus" Zone in one or two places. 
