Bracli'iopod Nomenclature. 529 



fioiii Colonna must be that. And I find it impossible to tliinlc 

 that the Bajocian fossil and Colonna's rejjresent the same 

 specie?. Bnth are biplicate, but there the similarity ends. 



This Bajocian fossil is peculiar to Normandy ; but Colonna 

 fif!;ured an Italian shell — he tells that it was found "in 

 Civitate Andrije." Now there are in the Tertiary (Pliocene) 

 beds of Italy various species which are much more like 

 Colonna's figure ; and there is in the Britisii Museum, Nat. 

 Hist., no. JS3458, a specimen from the Tertiary of Monte 

 ^lario, near Rome, wiiich might almost be the original 

 drawn by Colonna, so like is it to his figure. This specimen 

 is represented in the delineations given in Plate XII. 



Colonna's figure differs from the Terehratula Kleini of the 

 Bajocian of Normandy in having the plications more nearly 

 equal, running fuither up the valves, and in being much 

 more plicate for its smaller size. In the Bajocian shell the 

 frontal fold is much elevated, somewhat after the T. sella 

 fashion, and the dorsal sulcus is inconspicuously developed. 



Colonna's shell is distinguished from Terebr. perovalis, 

 (Sow., by having much more pronounced plications, extending 

 much furtlier up the valves. Again, it is distinguished 

 from Ttrehr. Phillrpsi^ Morris, by lacking the very pronounced 

 angular plications, by lacking the pronounced posterior 

 acumiuation, and by having an incurved beak : iu T. Phillipsi 

 the beak is not incurved, it projects straight posteriorly. 



There is one Mesozoic species to which Colonna's figure 

 has rather more resemblance than to those mentioned above. 

 This is T. Stephani, Dav. ; but its folds are not so strong, 

 do not extend so far back, and the shell is less elongate in 



I 

 snajje. 



The conclusion arrived at is that Terebratula terebratula — 

 that is, Colonna's shell — is not a Mesozoic species ; but it is 

 a Tertiary fossil, closely allied to species which have been 

 called Terebr. hisinuata, Lamarck, T. sinuosa, Brocchi, 

 T. ampulla, Brocchi, and even to 7\ grandis, Blumenbach. 

 These species may be said to belong to Terebratula, sensu 

 stricto ; but it may be doubted if any Mesozoic species would 

 belong to the genus in this very limited sense. 



The conclusions now arrived at confirm the results of 

 H. Douvill<3's investigations — t\\i\t Anomia terebratula, Linne, 

 is the genotype of Terebratula, that the species is a Pliocene 

 shell near to T. ampulla ; but they difl!er in the small detail 

 that the name Terebratula must be ascribed to MuUer, 1776, 

 and not to Klein, 1753. 



My application of the name diff'ers from Douvilh'-'s. He 

 would keep Terebratula for the biplicatc species (p. '1Q5), 



