92 
acquainted with in the Great Oolites. It consists of the shells 
of Lamellibranchs, chiefly Ostreea, embedded in a tenacious 
brown matrix of clay, with some apparently organic vegetable 
matter. The shells are all brittle, of calcareous material, crumb- 
ling almost ata touch. It reminds one of some post tertiary 
shell bands in the condition of the material. In working at the 
section we always called it the “organic band,” though 
properly it is a shelly clay bed. Mr Wethered who has 
examined this bed chemically, tells me it does contain 10°/, of 
organic matter, so that my naming of it was not altogether 
inappropriate. The shells apparently preponderate over the 
matrix in amount. 
This most remarkable bed may, I think, be taken as the 
lowermost extension of the Great Oolite proper, the beds below 
it corresponding to the Stonesfield slates. 
There is not in any of the sections anything like true 
Stonesfield slates, but beneath this well marked shelly clay, 
between it and the blue Fuller’s Earth are twenty feet of beds, 
which may belong either to the equivalents of Stonesfield slates 
or to the upper limestone beds of the Fuller’s Earth formation. 
The absence as yet of well preserved fossils, and my want of 
an intimate acquaintance with Fuller’s Earth, renders it imposs- 
ible to decide at present. 
The difficulty is felt most acutely in the next small cutting 
through a hill in lower Chedworth. 
THE LOWER CHEDWORTH CUTTING 
ft. ins. 
Oolite rubble... x ste 6-7 0O 
Band of shelly clay, ‘ribderenatinat ptababi to the shell band 
already noticed ac ae ae ee “0b ace - Toe OlaG 
Marly Oolite 52 ; cs 484 sie : oooh ZO 
Shelly limestones, with Oolitic sated and occasional soft pasty 
masses of CaCO3, and remains of Ostrwa acuminata... 15 0-16 0 
What these shelly Oolites are I will not here venture to — 
determine. They resemble in petrological character the upper 
beds of Great Oolite, but their fossils are different. 
