OF THE INFERIOR OOLITE OF GLOUCESTERSHIRE. 267 



accurately defining these beds as well as the oolitic limestone beneath 

 and the freestone above. 



The underlying or basement beds, which I propose to call the 

 Lower Limestone to distinguish them from the various limestone beds 

 above the Pea Grit, are to bo seen in numerous exposures on the 

 slopes of the Cottesyrold Hills, especially where the Cephalopoda-bed 

 is seen, as at Cam Liown near Dupsley, Coaley Wood, I'rocester Hill, 

 and Haresfield Hill, also at Birdlip, Crickley Hill, and Leckhampton, 

 and in most of the valleys near Stroud. 



The beds next above the Cephalopoda-bed are usually brown sandy 

 limestones in two or three beds, varying in thickness from five 

 feet at Cleeve Hill, near Cheltenham, to seven feet near Stroud and 

 Frocester Hill. The beds are locally fossiliferous near the base, but 

 much less so in their upper parts. Upon these brown beds there are 

 several beds of oolitic limestone, which are well described by Dr. 

 Wright, in the Frocester-Hill section, as " a coarse, light-cream- 

 coloured, gritty, crystalline oolite, traversed at intervals by shelly 

 layers extremely crystalline. A great part of the rock appears to be 

 composed of the fragments and plates of Crinoidea, the plates and 

 spines of Echinidse, and comminuted fragments of the shells of 

 MoUusca." In the upper portion these beds approximate to a 

 freestone character, and are well described by Dr. Wright, in the 

 Haresfield section, as " a close-grained freestone resembling the same 

 bed at Leckhampton, but becoming rather flaggy in the upper part." 



There is very slight difi'erence between these oolitic limestones, as 

 they appear in the sections at Procester Hill and Haresfield Hill, at 

 Crickley Hill, near Leckhampton, and in the Stroud valleys ; they 

 preserve the same lithological character throughout, except that at 

 Leckhampton they appear to be somewhat coarser in structure, 

 approaching the pisoKtic character, hence their being described in 

 that section as Pea Grit. One of the beds in the Stroud area is 

 remarkable for its great thickness ; in several quarries it varies 

 from 10 to 15 feet, a feature quite unusual in the lower Oolites and 

 is altogether different from the pisolitic character, which is that of a 

 rubbly rock. Upon the upper surface of these limestone beds, which 

 is usually quite plain and somewhat worn, the valves of a smaU 

 oyster are attached ; they are numerous but not so as to be contiguous. 

 I have found them in several localities, and they appear to extend 

 over the whole of the Stroud area. 



The thick bed of limestone contains seams of sheUy detritus, and 

 occasionally rather large rolled grains and small quartz pebbles, 

 rolled pieces of corals and Bryozoa, indicating a littoral deposit ; but 

 the general character of the rock is that of a white oolitic limestone. 

 If the presence occasionally of seams of coarse grains is held to 

 justify the inclusion of these beds in the Pea Grit or pisolitic lime- 

 stone, known as the ferruginous deposits, the greater part of the 

 Inferior Oolite must be so included, because the whole of the beds 

 contain locally coarse oolitic grains ; this is especially the case in the 

 Oolite-marl. 



