384 MR. L. RICHARDSON ON A SECTION [Aug. I903, 



contains, somewhat abundantly, a new species of Acanthotliyris : 

 the one referred to by Mr. Buckman as 



' an almost entirely globular species, with the spines in neat, regular rows, the 

 first some little distance from the beak : altogether a most distinct form.' 1 



Sometimes, however, the shaly deposit is absent, and then the 

 beds of the hemera Garantiance rest upon the subjacent sandy 

 limestone. The upper surface of this stratum is most irregular, 

 prominences, as much as 5 inches in height, projecting above the 

 general level of the bed. When the shaly deposit is absent this 

 limestone is simply riddled by Lithodomi, but I was unable to see 

 the degree to which it was bored when the former bed was about 

 3 inches thick : the face of the bed exposed when this deposit was 

 present above it showed no signs of any borings. Thus, even in this 

 small extent, there is a marked variation in the thickness of Bed 

 No. 4. This is due to the planing-down process of the Bajocian 

 Denudation, which has left it 4 inches thick at one end of the 

 quarry, but has reduced it to nothing at the other. Moreover, it is 

 noticeable that the south-western end of the quarry, where Bed 

 No. 4 is absent, is in the direction of the anticlinal axis. 



As regards the probable thickness and nature of the deposit 

 belonging to the ' intervening beds ' below the lowest stratum seen 

 in Cowley-Wood Quarry, evidence may be obtained from a study 

 of the section afforded in a quarry on the right-hand side of the 

 road from Birdlip to Cheltenham, near the Air-Balloon Inn. 



Section in Quarry near the Air-Balloon Inn. Thickness in 



Feet inches. 

 ( 1. Grey, sandy, shelly stone. 



2. Yellow, incoherent sands, with a layer of 

 stone near the base. 



3. Bluish and brown, clayey shale ; Tere- 



lyrat ula Bitchnani, T. crickleyensis 6 



..v.i.vi-URiT. i 4 Grey) gan ^ y slone ^ embedded in nockllar 



masses in a sandy marl ; thickness 



very variable, 4 to 10 inches 7 



Grey, sandy stone, several beds ; Acan- 

 thotliyris sp., Modiola 1 8 



f6. Slightly ironsbot, rubbly, marly stone; 



Lower Gryplwa, Modiola 3 2 



Tjrigoaxi-Grit. ] 7. Earthy layer ; Bhynchonella sp., a much- 

 crushed Aulacothyris Meriani 4 



UrrER Freestone. 8. Whitish, oolitic freestone ; (visible) 9 6 



Bed No. 5 of the Cowley-Wood section is doubless Bed No. 5 of 

 the above record, so that at the former locality a maximum thick- 

 ness of 5|- feet may be expected for the ' intervening beds ' : Bed 

 No. 4 of the above section being wanting at Cowley. 



The question now arises as to the extent of the area of the 

 Lower THgonia-Giit immediately below the Upper Trigonia-Giit. 



1 Quart. Journ. Geol. Soc. vol. li (1895) p. 447. 



