54 FIELD GEOLOGY. 



harder sand, and which, on being broken across, present 

 a sponge-like appearance. These evidently are, or were, 

 organisms of some kind, and are transferred to the fossil 

 bag for future investigation. 



The top part of the S. side of the pit is in soft marly 

 chalk, and as we dig down the slope this chalk gets 

 darker in colour, owing, it would seem, to the number 

 of green grains enclosed in it. Presently we come down 

 to the grey sand with green grains, but without having 

 noticed any sudden change where the one rock rests 

 upon the other. There is in fact a gradual passage from 

 the chalk into the sand, representing an equally gradual 

 change in the conditions of deposit. Still there is clean 

 chalk above, and clean sand below, therefore this pas- 

 sage portion represents the junction, and the line is con- 

 sequently drawn through that part of the map where 

 the pit is situated. These observations may be noted 

 in the following manner : 

 Date 187 . 



(Old) Sand-pit J furlong K of church. 



(About) 10 feet, fine light-coloured sand, with 



green grains, apparently horizontal, including a 



thin seam of broken sandstone (with ? sponges). 

 Chalk marl, with green grains, comes on at the 



S. side, and passes down into the sand. 



FOSSILS (determined in Part IV. Chap. iii.). 

 ( Terebratula 



Uiropr 

 Upper 



Green-sand. .,. , 7 

 Phcatula 



{^Ammonites 



