﻿BIVALVIA. 



103 



in his 'Brit. Assoc. Reports/ 1803. I have compared my Crag shell with recent speci- 

 mens of II. giganteus in the British Museum, and I cannot agree with those opinions. 

 M. Fischer has, in ' Journ. de Conch./ vol. x, p. 205, referred the fossil to Osfrea crispa, 

 Broc. (' Conch, foss. sub-Apen./ vol.ii, p. 567), which may possibly be correct ; but there 

 is no figure given of that species by Brocchi, and I have therefore left the Crag shell as 

 originally described. 



I have myself also found a single valve in the Red Crag at Ramsholt, subsequent to 

 the publication of the ' Crag Mollusca.' In the ' Geology of Norfolk ' this species is given 

 by S. Woodward as occurring rarely and in fragments at Thorpe, and the same thing is 

 repeated in the Norwich Crag list of his son Dr. Woodward, but I have not seen it myself 

 from the Fluvio-marine Crag. 



Pecten princeps, var. pseudo-princeps, S. Wood. Supplement, Tab. VIII, fig. 9. 

 Localities. Fluvio-marine Crag, Bramerton and Yarn Hill. 



When describing Pecten princeps from the Coralline Crag (' Crag Moll.,' vol ii, p. 32, 

 Tab. VI, fig. 1), I had occasion to refer to 'The Geology of Norfolk/ where at p. 44 

 that name is inserted, and against which is the letter a signifying abundant. I could 

 not then obtain the sight of a specimen, or ascertain from any of my collecting friends at 

 Norwich that they possessed this shell, and 1 thought possibly, from the general character 

 of the Fauna of the Norwich Crag, that fragments of P. Islandicus might have been mis- 

 taken for it. Since then the late Dr. S. P. Woodward informed me that two specimens 

 of P. princeps had been found near Norwich, and one of these (fig. 9 5), by the kindness 

 of the Committee of the Norwich Museum, has been transmitted to me for examination. 

 I have also had sent to me by Mr. Valentine Colchester (a son of my old friend Wm. 

 Colchester, on whose land at Sutton I have obtained so many Crag species), a specimen 

 which he found in association with Voluta Lamberti in the Fluvio-marine deposit at Yarn 

 Hill, and this also I have had represented, as it is the opposite valve to the one found at 

 Bramerton, while another specimen from the same place has been obtained by 

 Mr. E. Cavell. These different specimens present very considerable variation from 

 the typical Coralline Crag shell in the exterior ornament, so much so that I thought 

 at first sight they must be distinct ; my specimens of princeps, however, from the 

 Cor. Crag differ in the number and size of the rays from the one figured in 

 ' Min. Conch./ tab. 545, which I presume to be correct, and these both differ essentially 

 from the specimens now figured, more especially so from the one from Yarn Hill, which 

 possesses nearly two hundred imbricated rays, while those of mine from the Cor. Crag 

 have not half that number, even assuming an intermediate ray to be elevated into a primary 

 one. 



