512 ME. M. 0DLING ON THE [Oct. I913, 



EXPLANATION OF PLATES XLVII & XLVIII. 

 Plate XLVII. 

 Fig. 1. Exposure in L ; pper Green-Hill Quarry, eastern end. 

 2. Exposure in Lower Green-Hill Quarry. 



Plate XLVIII. 

 Fig. 1. Cornbrash from Hanborough Quarry, near the railway-station ; X 16. 

 Two large ooliths, probably derived, occur near the top ; the rock 

 consists, for the greater part, of small shell- and echinoderm-frag- 

 ments in a somewhat marly matrix; echinoderm-fragments are most 

 abundant towards the bottom and left-hand edges. 



2. Stonesfield Slate enclosing a pebble ; X 16. The ' slate ' consists of 



small shell-fragments and quartz-grains, together with numerous- 

 ooliths and one large echinoderm-fragment near the top towards the 

 right; the pebble consists of small shell-fragments and abundant 

 quartz-grains, without any ooliths. 



3. Transverse section of the annelid-tube described on pp. 503 & 504 ; 



X 4^. This shows the concentric arrangement of the particles ■„ 

 the irregularly-arranged material on the left-hand half of the central 

 portion has evidently fallen in. 



4. Longitudinal section of the above, showing the arrangement of the- 



fragments parallel with the length of the tube. X 4^. 



Discussion. 

 The Secretary read the following letter, received from Mr. S. S,, 

 Buckman : — 



'The abstract of the paper on the Bathonian rocks of the Oxford district 

 appears to indicate that the Author has accomplished an important piece of 

 work. The geology of that district is little known in detail, except from a 

 paper by Mr. E. A. Walford read before, but unfortunately not published by, 

 the Society L — a paper written before (he cuttings on the new railway gave a 

 further insight into the sequence, which is a great advantage to present-day 

 investigators. The present Author seems to have been able to confirm 

 Mr. Wal ford's, sequence. 



' When the Author states that " although no definite zones can be formulated, 

 the different horizons are readily recognizable by their assemblage of fossils,"' 

 he seems to be under some misapprehension as to a zone. The different 

 assemblages of fossils are the local zones: their correlation with the zonal 

 system of the similar strata on the south-west should present no difficulty, and, 

 if stated, would give to the paper greater value and a wider interest. Besides, 

 ammonites from these strata have been obtained by other investigators, wbich 

 would yield further evidence for fixing zones. 



' A particular interest in the strata of this district is the position of the 

 Neseran Beds, already ascertained from Mr. Walford's researches. They link 

 up the marine Fullers' Earth strata of the south-west with the tipper 

 Estuarine deposits of Yorkshire, and thus enable the date to be fixed for the 

 Yorkshire beds. 



' The Author's use of the term ' Concinna Beds' is inadvisable. Bhyncho- 

 oiella concinna is a species of the Cornbrash. Various more or less concinva- 

 like lUrynchonellm are found in earlier rocks, but to give them the name of the- 

 Cornbrash species is misleading. There is a somewhat large inconstant] form 

 Bhynchonella which occurs in, and is characteristic of, certain Fullers' Earth 

 deposits of the Ardley Cutting. So far as I know, it does not occur in other 

 districts; but it should not be called Eli. concinna.' 



1 [This paper, under the title of ' Some New Oolitic Strata in North Oxford- 

 shire,' was afterwards privately printed : Buckingham, 1906.] 



