﻿ADDENDUM. 



183 



and nomenclature to arbitrary lines of separation, it does not seem to me expedient in 

 the face of the difference pointed out to regard this species as living. There is so much 

 uncertainty respecting the shells that are to be referred to unisulcata or plicosa that I 

 have retained the name originally given to the Crag species. 



Scalaria semicostata, /. Sowerby. Addendum Plate, fig. 1. 



Scalaria semicostata, J. Sow. Min. Conch., tab. 577, fig. 6. 

 Locality. Red Crag. 



A beautiful and perfect specimen of Scalaria has been put into my hands by Mr. 

 Charlesworth, but I believe it to be a derivative from one of the older tertiary formations. 

 This specimen came originally from Mr. Whincopp, who had it from one of the diggers 

 for " Coprolite," I presume from Sutton, whence he had most of his specimens. 



Two figures are given by Mr. James Sowerby, tab. 577, fig. 5, as S. reticulata [Turbo 

 reticulatus, Brander), V, fig. 6, as semicostata. In the very great accuracy of Mr. 

 James Sowerby's general figures I have perfect faith, and I believe the two to be 

 distinct. 



M. Deshayes has figured and described a fossil from the " Sables moyen," ' An. 

 sans Vert, du Bas. de Par.,' vol. ii, p. 343, PI. 23, figs. 13 — 16, under the above name, 

 which seems also to correspond with our shell. The specimen figured in 'Min. Con.,' 

 Tab. 577, fig. 6, cannot now be found. 



Scalaria communis, Lam. Addendum Plate, fig. 5. 



Scalaria communis, Lamark. An. sans Vert., vol. vi, p. 228. 

 — — ,, Jeffreys. Brit. Con., vol. ii, p. 91. 



Locality. Post-glacial, March. 



An imperfect specimen of this well-known British species was obtained from the 

 March gravel by Mr. Harmer, and sent to me ; and as no doubt perfect specimens will 

 hereafter be obtained from that locality, I have had the figure drawn from a recent 

 specimen. 



This species is given as from the Red Crag by Mr. A. Bell in his list of the 

 " English Crags," as also by Mr. Jeffreys in his list attached to Mr. Prestwich's Red Crag 

 paper, but I have not been able to confirm these references. 



