Vol. 63.] OF THE BATH-DOULTINGr DISTRICT. 407 



which Mr. Winwood thinks — and, no doubt, correctly so — belong 

 to the Upper Lias. 



Mr. S. S. Buckman found in the Lyncombe cutting a mass of the 

 same bed, but was able to recognize in it deposits laid down during 

 three hemerae — those of falciferum, bifrons (' comimme-zone'), and 

 striatulum. 1 This bed, from 1J to 2 feet thick, is the local 

 Cephalopod-Bed. Above it come the Midford Sands, which are 

 capped by the equivalent of the Upper Trigonia-Grit. 



The Midford Sands here are obviously -post-striatuli, and since 

 Mr. Buckman obtained from a ' sand-burr,' fallen out of the lower 

 portion, a specimen of a Pseudogrammoceras (Ps. cf. Stmchmanni 2 ), 

 the lower portion must be of Struckmanni hemera. The top-portion, 

 Mr. Buckman informs me, may be of later date. 



Nowhere in this area have I found ammonites in the upper portion 

 of the ' Sands/ and therefore it is impossible to date them with 

 absolute certainty. At Timsbury Sleight, however, where they are 

 only 5| feet thick, the Midford Sands are -post-Struckmanni, 

 because ammonites indicative of this hemera occur in the top- 

 portion of the Cephalopod-Bed. Here they are probably of dispansi 

 hemera. 



The Midford Sands, of course, derive their name from Midford, 

 and are well exposed on the south of the lower portion of the combe 

 south of Combe Down — that at the mouth of which, adjoining 

 Tucking Mill, is the house where William Smith lived, while he was 

 engaged in the construction of the Somerset Coal Canal in 1798- 

 1799. 



South of Midford Station, by the side of the main road, is the 

 section recorded in Table II (facing p. 408). Mr. W. H. Hudleston 

 correctly identified, in a broad way, the strata exposed here 

 with their equivalents in the Cotteswold Hills, 3 holding that the 

 ' lower stage ' (Upper Trigonia-Grit) probably represented the 

 Upper Trigonia-Grit of Stroud and Cheltenham ; but apparently 

 could not reconcile himself to the magnitude of the gap between 

 that deposit and the underlying Midford Sands. In consequence, 

 he stated that, as the whole of the Lower Division of the Inferior 

 Oolite was absent as a limestone, it ' may possibly be represented 

 by the upper portion of these same Midford Sands.' This, however, 

 we now know is not the case ; all the Inferior-Oolite beds which 

 come — where the sequence is complete — between the deposits of 

 Garantiance and Moorei hemerae are wanting. 



James Buckman also thought that the sands of Midford repre- 

 sented a limestone-deposit of certain other localities ; but, instead 

 of regarding the upper portion as possibly equivalent to the Lower 

 Division of the Inferior-Oolite Series as Mr. Hudleston did, he 

 paralleled them with the Freestone of Doulting and the Building- 



1 Quart. Journ. GeoL Soc. vol. xlv (1889) p. 447. 



2 — Grammoceras fallaciosum of the section ibid. p. 448. 



3 'Monogr. Brit. Jurassic Gasteropoda' pt. i, Palaeont. Soc. (1887) pp. 55-56. 



