The rarity of drifts in the Crouch Valley has been often remarked. The only river gravel marked in it on the Geological Survey Map, sheet I N.E., is a small patch at Little Hayes, a couple of hundred yards north of the Crouch, and 1¼ miles S.S.W. from Woodham Ferrers railway station. In the Evolution of the Essex Rivers (1922, p. 47), an analysis of the five chief constituents, based on a collection made by Mr. H. J. Nicholson, recorded some Jurassic sandstones which I regarded as probably derived from the boulder clay on hills about three miles north and north-west. A visit to the pit last year in order to obtain larger specimens of the Jurassic material yielded various cherts; one is a typical Rhaxella chert, which has not been previously recorded so far to the south-east. A thin bedded oolitic chert, which was different to any that I knew, was submitted to Mr. H. C. Sargent with the inquiry whether it might be one of the Carboniferous cherts of the Midlands. Mr. Sargent identified some of the inclusions as silicified oolitic grains, and rejected the rock as Midland Carboniferous. The specimens and slides were also kindly examined by Professor Boswell, who showed them to Mr. E. T. Dumble for comparison with the Rhaxella chert found by him in the Crag; they also did not know any similar rock. The specimens were then sent to Dr. Morley Davies, who confirmed the identity of the one specimen with the ordinary Oxford-Buckingham Rhaxella chert, and has, in the previous note, described the other as a Rhaxella chert in which the spicules are the nuclei of oolitic grains.