OF NORFOLK AND SUFFOLK. 321 



have they in general the red ferruginous colour by which the 

 fossils of the upper crag of Suffolk are tinged. I may how- 

 ever remark, that the fossils of the Norwich crag have also, in 

 some places, acquired a yellow ochreous colour, so that the 

 presence of this character does not at once stamp a shell as 

 having been derived from the more ancient bed. When there 

 is only evidence of a few fragments of a remarkable shell, such 

 as Hinnites Dubuissoni, or when I have only met with one 

 bouldered specimen, as of Murex alveolatus, and that stained 

 red, I have rejected them as spurious without hesitation. — 

 The greater number of specimens of the Fusus contrarius 

 which are broken or bouldered, may also doubtless be refera- 

 ble to the same source. This last point however is one of 

 minor importance, as a conchologist may satisfy himself, by 

 referring to an extensive series, such as Mr. Wood possesses, 

 that the Fusus contrarius is merely a sinistral variety of Fus. 

 striatus, a fossil which properly belongs to the Norwich crag, 

 and of which Capt. Alexander posseses a reversed specimen 

 from Bramerton, of the ordiuary striated variety with angular 

 whorls. The individual last mentioned is quite perfect, and 

 free from ferruginous stains. 



No species of Terebratula was enumerated in Woodward's 

 list of the Norfolk crag shells, although the species allied to, 

 if not identical with, Ter. pslttacea, is by no means rare. On 

 the other hand, Woodward mentions Ter. plicatilis as being 

 washed out from the chalk into the crag. Mr. Charlesworth 

 also has spoken of various species of Terebratula, and other 

 chalk fossils, as of frequent occurrence in the crag of Norfolk. 1 

 I collected many Terebratulce, of the recent species before 

 mentioned, without ever happening to meet with any derived 

 from the chalk, the introduction of which therefore appears to 

 me to have been a local accident. 



It becomes a question of greater delicacy and difficulty 

 when only one entire specimen, or a small number of broken 

 specimens, of a well-known shell of the red or coralline crag 

 have been met with. In this predicament the following ten 

 species appear to stand at present. 



1 Voluta Lamberti Cardita concentrica 



Cassis bicatenatus Pecten plebeius 



Murex costellifer Astarte oblonga 



Buccinum elongatum Lucina obliqua 



5 Cardium edulifium 10 Mactra arcuata 



To exclude all these because of their extreme rarity, would, 

 I think, be somewhat rash, because we have as yet only soli- 



1 Phil. Mag. No. 42. p. 468, Dec. 1835. 



