4.46 Mr. T. Davidson on Lamarck’s species of 
species belonging to the greensand of Mans. M. D’Orbigny ad- 
mits this species, which he places in his genus Terebratella, and 
states in vol. iv. p. 116 of his ‘ Pal. Franc.’ that the Terebratula 
truncata, Sow., 1826, M. C. vi. p. 71. pl. 537. fig. 3, belongs to 
a distinct species, and not to Terebratula Menardi, Lamk., and 
to which he gives the new name of Terebratella Asteriana, as he 
cannot retain the name of Ter. truncata, it having been given by 
Linneus to another shell. There exists however some doubt if 
on this point M. D’Orbigny’s opinion is correct ; the general 
form in T. Menardi is often, though not always, broader than in 
our Faringdon specimens, the ribs sharper, and depression of the 
dorsal valve deeper, and bounded laterally by sharper ridges, 
lines of growth less strongly marked, mesial longitudinal process 
on inner side of ventral valve shorter and not so strong. La- 
marck’s specimens do not appear to vary so much in form as our 
Faringdon specimens, and have a much thinner shell; but on 
examining with great care a numerous suite of specimens of these 
species, both in the collection of the British Museum and those 
collected by myself in both localities, Messrs. Waterhouse, 
Woodward and myself believe that the species may be the same, 
and that the greater or less thickness of the shell might arise 
from the difference of the water in which they lived; the Fa- 
ringdon specimens being much worn, so that the plaits must 
have been much sharper in the living state. 
51. Terebratula decussata, Val. and Lamk. PI. XIV. fig. 51. 
T. testa subpentagona, subconvexa, valva majori canaliculata, striis 
transversis tenuibus longitudinaliter decussantibus: nate subpro- 
ducta foramine magno. 
Obs. Lamarck refers to the ‘ Encye. Méth.’ pl. 245 a, B, ¢. 
However, in 1811, before Lamarck, Parkinson described and 
figured this species in the 3rd vol. of his ‘Organic Remains,’ 
pl. 16. fig. 5, under the name of Terebratula coarctata, which name 
must be preserved to the species, as M. D’Orbigny has done in 
his ‘ Prodrome,’ vol. i. p. 316, and Lamarck’s name placed among 
the synonyms along with Sowerby’s Terebratula reticulata, M. C. 
tab. 312. fig. 5,6. The Ter. coarctata is very common in the 
Forest marble and Bradford clay. The only specimen Lamarck 
had is in B. Delessert’s collection. 
52. Terebratula spinosa, Val. in Lamk. Pl. XIV. fig. 52. 
T.. testa globosa, dilatata: sulcis parvis spinosis: nate brevissima 
acuta. 
Obs. This species seems to have been first named by Smith, 
‘ Strata identified by Fossils,’ 1816 or 1817. Deshayes and Morris 
also refer to Knorr, Test. Diluv. It is a well-known inferior 
