﻿144 



SUPPLEMENT TO THE BRTTISH 



Nunney and Whatley, near Frome, be really distinct, we must add Sowerby's name, and 

 not that of Smith, to the variety or species. 



Mr. E. Deslongchamps in his " Notes sur le Terrain Callovien," vol. 4 of the 

 ' Bulletin of the Linnean Society of Normandy/ retains T. reticulata, Sow., for a shell 

 much resembling Smith's figure. He adds that it appears first in the bed characterised 

 by Ostrea Knorrii, when it much resembles T. coarctata ; but when found in higher beds 

 of the Callovian period it widens more and more, the sinus becomes broader, and the 

 shell is at last almost smooth. 



Sowerby states that in T. coarctata "the minute bristles that render the surface hispid 

 are short, often tubular, and are situated upon the angles of intersection of the two sets 

 of lines, of which the longitudinal are elevated and cut by the transverse;" and that in 

 T. reticulata " the ridges are not much elevated, and the spines hardly rise above the 

 surface, but appear as if pressed into it." 



M. Koechlin-Schlumberger observes, in reference to the reticulated surface, that the 

 number and strength of the striae are much greater in some specimens than in others, just 

 as is seen to be the case with Bh. spinosa. That in some specimens they are coarse and 

 fewer in number, and in others more numerous and much less sharply defined. 



Mr. J. F. Walker considers T. coarctata from the Bradford Clay and Great Oolite 

 near Bath to be specifically distinct from T. reticulata, Sow., from the Inferior Oolite of 

 Frome. It may therefore be desirable to retain the name reticulata, Sow., as at least 

 a named variety. A large example of T. coarctata (Sup., PI. XIV, fig 18) in the 

 Museum of the School of Mines is stated, on the tablet, to be from the Cornbrash of 

 Handthorpe, near Bourn, in Lincolnshire. 



119. Var. reticulata, Sowerby. Dav., Ool. Mon., PI. XII, fig. 15 ; Sup. PI. XIV, 



figs. 20, 21. 



Terebratula reticulata, Sow. Min. Con., tab. 312, figs. 5, 6, Nov., 1821. 

 Sowerby describes his species in the following words : 



" Spec. Char. Obovate, gibbose, subhispid, decussated ; front obscurely 3-sided ; 

 lesser valve convex ; larger valve obtusely biplicated, with a shallow channel between the 

 ridges. 



"Terebratula reticulata? Smith. 



" The general form of this is much rounder than the last ; the ridges are not much 

 elevated, and the spines hardly rise above the surface, but appear as if pressed into it ; it 

 is also a larger species. 



