TRANSACTIONS. 
O71 Campylodiscus^ ^c. By H. K. Greville,, 
LL.D., F.R.S.E., &c. 
(Communicated by F. C. S. Eoper, F.L.S., &c.) 
The short paper whicli I have now the honour of laying 
before the Society contains descriptions of new species of 
Campylo discus, of singular beauty and great rarity. The 
materials have been accumulating on my hands for a con- 
siderable time ; and as the illustrative figures are sufficiently 
numerous to fill a plate^ I venture to ofi"er them for publi- 
cation. Amongst the drawings I had prepared^ was one of 
Campylo discus striatiis, Ehrenb. ; but Mr. Brightwell has sub- 
sequently well represented that species in Plate IX^ vol. vii^ 
of the ' Microscopical Journal.^ It required to be correctly 
figured ; for the original engraving in Ehrenberg {' Amer./ 
tab. iii^ vii_, fig. 13), than which nothing can be more obscure, 
was the only one we possessed, for that given by Kiitzing 
C^Bacill./ tab. xxviii, fig. 11) is merely a copy. Although 
very difficult to reconcile such a figure with the beautiful 
diatom itself, I believe Mr. Brightwell is correct in having 
done so. His station, as well as that given by Ehrenberg 
and Kiitzing, is Vera Cruz. My specimen was obtained from 
the washings of small algae from Jamaica. 
Campylodiscus Normanianus, n. sp., Grev. — Valve circular ; 
canaliculi 3 to 4 in '001", the centre occupied by a circum- 
scribed linear-oblong depression, across which the canaliculi 
pass until they nearly meet. Diameter -0045". PI. I, fig. 1. 
In cleanings of Spondyli ; George Norman, Esq. 
I have much pleasure in dedicating this very fine diatom 
to my friend, Mr. George Norman, of Hull, who directed my 
attention to it. He informs me that the shell from which he 
obtained the scrapings, yielding not only the present but two 
VOL. VIII. / 
