CYRTINA. 



73 



character is but rarely exhibited in the generality of specimens, on account of their external 

 surface being considerably worn, so that the appearance can be detected only on those 

 portions of the shell which are in their perfect condition. 



Loc. Professor M'Coy's specimens were derived from the impure lower Carboniferous 

 limestone of Kendal, Westmorland, where the species does not appear very rare. 



Having now completed the description and illustration of all the species of Spirifera 

 Spirifcrina, and Cyrtiiia, that are known to me as positively occurring in the carboniferous 

 strata of Great Britain, it will be seen that not more than about thirty-one or two have been 

 retained out of one hundred and seventeen that had been described or mentioned by various 

 authors. A searching investigation has led me to infer that about eighty-six of the published 

 names are made up of synonyms, of species not positively known to occur in Great Britain, or 

 of Carboniferous shells erroneously identified with Devonian species, as well as of specimens 



belonging to other genera.^ 



' The following is a list of 117 so-termed British 

 work are printed in roman type, the synonyms, &c., in 

 before the more doubtful species : 



? Spirifera acuta, Martin. 



— attenuata. Sow. 



— aperturata, ^ch\oi\\. Not carboniferous. 



— arachnoida, Phil. Strophomena. 



— bisulcata, Sow. 

 ? — bicarinata, M'Coy. 



— Bouchardii, Murch. Not carb. 



— carbonari us, M'Coy. 



— Crispa, Linnaeus. Not carb. 



— costata. Sow. Not carb. 



— connivens, Phil. Orthis. 



— clatharata, M'Coy. 



— calcarata, G. Sow. Not carb. 



— convoluta, Phil, 

 crassa, De Koninck. 

 cuspidata, Martin. 

 choristites, V. Buch. 

 carlukiensis, Dav. 

 crenistria, Phil. Strophomena. 

 decemcostata, M'Coy. 

 decora, Phil, 

 distans. Sow. 

 dorsata, M'Coy. 

 duplicicosta, Phil. 

 disjunct a, Sow. Nc carb. 

 elonffata, Phil 

 exarata, Fleming. 



? 



? 



7 



Carboniferous Spirifera ; the species adopted in this 

 italic letter, and a point of interrogation is placed 



Spirifera expansa, Phil. Athyris. 



— elliptica, Phil. 



— extensa. Sow. Not carb. 



— faseiculata, M'Coy. 

 ? — fusiformis, Phil. 



— furcata, M'Coy. 



— ficiyer, Keyserling. 



— filiaria, Phil. Orthis. 



— glabra, Martin. 



— ghbularis, Phil. Athyris. 



— grandicostata, M'Coy. 



— glabristria, Phil. Athyris. 



— giyantea. Sow. Not carb. 



— grand(Eva,V\ri\. Not carb. 



— heteroclytus, Def. Not carb. 



— histericus, Schloth. Not carb. 



— humerosa, Phil. 



— hemisphcerica, M'Coy. 



— incisa, Goldf. 



— imbricata, Sow. 



— insculpta, Phil. 



— integricosta, Phil. 



— inornata. Sow. Not carb. 



— Kleinii, Fischer. 



— Koninckiana, D'Orb. 



— lineata, Martin. 



— linguifera, Phil. 



10 



