18 SUPPLEMENT TO THE CRAG MOLLUSCA. 
Buccinum unpatum, Linné. Crag Moll., vol. i, p. 35, Tab. III, fig. 12. Supplement, 
Malb., II. 
Localities. Red Crag, Sutton. Upper Glacial, Bridlington? Post-glacial, Kelseahill 
gravel (Jeffreys), and Nar brick-earth (Rose). 
Localities of var. tenerum.—Red Crag passim. Fluvio-marine Crag, Bramerton and 
Thorpe; Chillesford bed, Bramerton and Horstead. Middle Glacial, Billockby and 
Hopton. Post-glacial, The March gravel. 
In the ‘Crag Mollusca’ I have figured three different forms under the specific name 
of wadutum, and I have here introduced three more. 
Fig. 2, Tab. II, Supplement, appears to resemble what has been called A. 
Grenlandicum. Fig. 3 of the same plate is an extreme variety as to its ornamentation, 
which I will call Buc. undatum, var. clathratum. Buc. tenerum of ‘Min. Conch.,’ t. 486, 
figs. 8, 4, which the late Dr. S. P. Woodward in his list of Norwich Crag shells refers to 
cyaneum ? may possibly be distinct. Fragments of ¢enerwm (principally of the columella) 
occur in the Middle Glacial sands of Billockby and Hopton Chiff, while perfect specimens 
of it exactly resembling those of the Red Crag and of all ages abound in the Post-glacial 
Fen gravel of March. ‘The constant features maintained by ¢exerwm in the Crag, when 
found to recur in so modern a formation as the Fen gravel, impress me with the belief 
that this is a distinct species. Buc. wndatum (‘Crag Moll., Tab. TIT, fig. 12, ¢) is very 
rare in the Crag, while the form ¢exerwm swarms in it. In the numerous specimens 
sent to me from March by Mr. Harmer I have not seen the true form of B. wadatum, 
and as this Post-glacial gravel of March presents a more Arctic character than the 
present British seas I am disposed to believe B. tenerum may be B. cyaneum. 
Supplement, Tab. TI, fig. 5, represents a specimen from the Red Crag of Butley which 
has much perplexed me. There is an angularity in the upper part of the volution, below 
which it is contracted. The upper part of the volution is slightly striated, and there are 
some striz on the base or lower part of the body-whorl, with very faint indications of 
undulations upon the spire, like those of wzdatum, with reflected imbrications upon the 
columella. The spire is much depressed, but it looks like a distortion, and I have 
considered it as such for the present. I will call it B. undatum, var. ovulum. The axis 
of the shell is 4%ths of an inch. 
Purpura apitius, Linné. Crag. Moll., vol. 1, p. 36, Tab. IV, fig. 6. 
Localities. Red Crag passim. Fluvio-marine Crag, Bramerton and Thorpe. Lower 
Glacial, Belaugh, Rackheath, and Weybourne. Middle Glacial, Billockby and Hopton. 
Post-glacial, Kelsey Hill and March. 
The variety crispata occurs in the Chillesford bed at most of its localities and in the 
Lower and Middle Glacial sands. In the Middle Glacial the form imcrassata is in 
