RED AND NORWICH CRAGS. 
117 
At Blake’s pit, Brnmerton, Scrohicularia is abundant, though 
exceedingly rare in the adjoining pit on the Common. Calyptrcea 
chinensis and Loripes divaricatus abundant in an adjacent lane¬ 
cutting, in Kirby Bedon parish, are not nearly so common in 
either of the pits at Bramerton. At Arminghall Mactra ovalis 
is so abundant that Dr. J. E. Taylor well observed that the 
deposit might be called t\\Q Mactra bed. In one pit at Wroxham, 
Astarte borealis is particularly common, Tellina halthica is rare ; 
while at Belaugh the reverse is the case. 
Although the term Mammaliferous Crag was applied by Mr. 
Charlesworth, from the occurrence in it of the remains of masto¬ 
don, elephant, deer, &c., yet these remains are so rare in the Crag 
that it falls to the lot of few collectors to obtain specimens them¬ 
selves ; and most of those which enrich our public and ])rivate 
collections were obtained from the workmen engaged in digging 
the Crag. Probably not more than twenty teeth of the Mastodon* 
have been obtained, but this form possesses peculiar interest from 
the fact that it has not at present been discovered in the Forest- 
bed Series. 
It is the general opinion, and one confirmed by the testimony of 
the workmen, that the mammalian remains are most abundant in 
the lower portions of the Crag. Its basement bed consists of a 
layer of more or less rolled flints with a few pebbles of quartz and 
quartzite, embedded in a clayey or sandy matrix, and has been 
termed by Mr. Gunn the Mammaliferous Stone Bed,’’ from the 
fact that so many bones have been obtained from it. 
The bones found at Thorpe, where Mr. H. B. Woodward has 
obtained numerous specimens, are, however, most abundant im¬ 
mediately above the Stone Bed, few occurring in it. During 
recent years the Crag has been extensively removed and the 
Stone Bed has been well exposed. On one occasion a portion of 
the tusk of an Elephant was found on the Stone Bed. Still the 
specimens are sufficient^ near the Stone Bed to support the state¬ 
ment that bones are most abundant in the lower portions of the 
Crag, though Mr. Woodward does not consider that they have 
any special connection with the Stone Bed, or that this bed ought 
to be separated from the Crag. 
Instances are on record of Mammalian remains having been 
obtained at some distance above the base of the Crag, as at Sur- 
lingham, where the tooth of a Mastodon was found by the 
workmen in a bed of sandy gravel just above the mass of lami¬ 
nated clay so largely worked. The exact s[)Ot from which this 
specimen was obtained was pointed out by Mr. Gunn, in 1873, 
who explained that the specimen showed signs of having been 
derived from some lower bed, for adhering to the tooth, were 
portions of a hard gravelly matrix, which was distinct from the 
Noticed by Parkinson (1811), Organic Remains, p. *149. A grinder of the 
Mastodon found at Whitlingham was figured, in 1816, by William Smith in his 
Strata Identified by Organized Fossils. 
