80 
eeb crag. 
apparently disconnected masses of which are imbedded in it here 
and there. Notwithstanding certain difficulties, these authors now 
accept Mr. Whitaker’s view that this sand is Crag deprived of its 
shells by the infiltration of water, casts of the shells being left 
where there is ironstone ; for in one case a layer of pebbles 
extends continuously from the shelly Crag into the sand. They do 
not agree with Prof Prestwich in referring this sand to the upper 
or Chillesford division of the Red Crag, because the casts of 
shells in the ironstone are not of species characteristic of the 
newer (or Butley) part oi* * * § the Red Crag or of the Chillesford 
Beds. 
In the same year, when describing the patches of Red Crag at 
Walton Naze, Beaumont, and Harwich,* Mr. Whitaker suggested 
that the shell-less sand above was but the result of the alteration 
of the shelly Crag below, and in a note devoted to this subject! 
showed that what had been supposed to be a line of erosion was 
only one of irregular alteration, the lines of false-bedding of the 
shelly Crag being sometimes continued into the sand above ; that 
this irregular dissolving away of the shells explains the apparently 
isolated masses of Crag in the sand, and that this unfossil if erous 
sand extended beyond where the shelly Crag had been observed. 
In 1877 Mr. E. Charlesworth, in reprinting a notice, by Prof. 
Lankester, of the Crag fossils in the Ipswich Museum (from the 
Suffolk Chronicle of August 4), recurred to the subject of the pro¬ 
spective exhaustion of the nodule-bed, and in the following yearj 
he gave a note on English Crag History, referring especially to his 
earlier w^ork, and remarking that the Red Crag is the record of a 
past state, like that where our Crag cliffs are now being washed 
by the sea, in the bed of which new formations are in progress, 
partly made up from remains of the present fauna, and partly 
from the fossils carried away from the land. 
In the same year (1878) Mr. Whitaker described the sections 
of the westerly extension of the Crag (at Sudbury)§ noted in his 
paper of 1874, and suggested that possibly some sands that had 
been classed as Drift might turn out to be Crag, a question also 
alluded to in a later Memoir. || 
In 1879 S. y. Wood in his Second Supplement to the Crag 
Mollusca,^ treated of the introduction into Crag lists of new 
species on unsatisfactory evidence, either from doubtful identifi¬ 
cation, or as being simply derivatives, and gave an addition to the 
Synoptical List of Mollusca in the First Supplement. 
* The Geology of the Eastern End of Essex . . . (^Memoirs of the Geological 
Survey'),])^. 10-16. (1877.) 
f Quart. Journ. Geol. Soc., vol. xxxiii. pp. 122, 123. 
X Eossil Exploration of Suffolk Crag (Orford Castle) and Hampshire Eocene 
Cliffs, pp. 8. 8 VO. London. Privately printed, 1878. 
§ The Geology of the N.W. Part of Essex . . . (^Memoirs of the Geological 
Survey), pp. 30, 31. 
II The Geology of the Neighbourhood of Stowmarket, {Me7noirs of the Geological 
Survey), p. 5. (1881.) 
^ Palaontographical Soc., pp. i., il., 54, 55. 
