BIVALVIA. 103 
in his ‘ Brit. Assoc. Reports, 1863. I have compared my Crag shell with recent speci- 
mens of /. 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 Ostrea crispa, 
Broce. (‘ 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. 
Prcren 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 u, 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 @ 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. Ls/andicus 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 4), 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 Volwta Lamberti in the Fluyio-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 bas 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 Mill, 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. 
