On the Internal Structure of Terebratula pectunculoidcs. 449 



pi. 246. fig. 1 a, b, but on inspecting that figure^ one might be 

 led to consider that the species must be either Terebratula acU" 

 minata or Ter. Meyendorfii, De Verneuil, Geol. of Russia. How- 

 ever, we find in B. Delessert^s collection a specimen of Ter. acu- 

 minata with that name written by Lamarck, to M^hich he added 

 ("non decrit"). In a letter I lately received from M.Valenciennes, 

 the original describer of the species, he distinctly states that his 

 Ter. spirifera is the same shell as that subsequently described 

 and figured by Sowerby in the ^ M. C. ^ under the name of Spi- 

 rifer striatus, which he proves by sending me the original speci- 

 men given to him in 1817, when in London, by the author of 

 the ' Mineral Conchology,^ a restored figure of which I give in 

 my PI. XV., M. Valenciennes^ specimen being much broken and 

 incomplete. It is, as every one knows, a common carboniferous 

 shell in many countries, and has also received many names. 

 Sowerby published it in 1821, and M. Valenciennes in 1819 ; but 

 I do not know how far the last-mentioned author^s species would 

 have a right to priority over Sowerby ^s, on account of the false 

 reference given to quite another shell in the 'Ency. Meth.^ It 

 is however certain, from the type specimen before me, as well as 

 from the Latin description, " transverse dilatata, sinris," that the 

 describer had in view the same shell described afterwards under 

 the name of Spirifer striatus. M. Deshayes, in his new edition 

 of Lamarck, was led naturally into the mistake, as any one would 

 have been. He states that '^ this species is the same as Ter. acu- 

 minata of Martin and Sowerby, and the figure referred to in the 

 ' Ency. Meth.^ would lead one to believe so ; but as it is very bad, 

 and only inexactly represents Ter. acuminata^ it has not prevented 

 me adding here the species intended." 



XXXVIII. — On the Internal Structu7^e of Tevehratwla pectuncu- 

 loidcs, Schl., Terebratula pulchella. Nils., and Terebratula 

 Deslongchampsii, nob. By Thomas Davidson, Esq. 



[With a Plate.] 



As my intentions are to publish shortly some views relating to 

 the internal calcareous support of the ciliated arms in Terebratula 

 and allied genera, I have simply given in PI. XV. illustrations of 

 two of these supports, hitherto unfigured. 



Fig. 4. PL XV. represents Ter. pulchella, Nils., and its internal 

 calcareous loop, from a specimen derived from the chalk of Bel- 

 gium, now in the cabinet of M. Deslongchamps. 



Fig. 5. PI. XV. represents Ter. pectunculoidcs (Schl.) and its 

 internal calcareous support considerably enlarged, from two spe- 



Ann. ^ Mag. N. Hist. Ser. 2. Vol. v. 29 



