CYRTINA. 75 



the above-named doubtful species will be found to be synonyms of some of the thirty 

 already described, and that even three or four of this number may require, upon more 

 extended examination, to be reduced to the rank of varieties. 



The species of British Spirifera, Sjnriferina, and Cyrtina at present knov^n might 

 perhaps be arranged in the following order. 



1. Spirifera STRIATA, Martin, sp. Pet. Derb., tab. xxiii, 1809; Dav. Brit. Foss. Brach., part v, 

 pi. ii, figs. 12 — 21 ; pi. iii, figs. 2 — 6 = Spirifera, Lamarck = attenuata' 

 J. de C. Sow. = princeps, M'Coy = Clatharata, M'Coy. 



2. — MOSQUENSis, i^i'sc^ey de Waldheim. Programme sur les Choristite, p. 8, No. 1, 1837; 



and Dav., pi. iv, figs. 13, 14, and pi. xiii, fig. IG = Sowerbyi and 

 Kleinii, Fischer = incisa, Goldfuss = Choristites, V. Buch. = prisons, 

 Eichwald. 



3. — HDMEROSA, Phillips. Geo). York., vol. ii, pi. xi, fig. 8, 1836 ; and Dav., pi. iv, figs. 



15, 16. 



4. — DUPLicicosTATA, Phillips. Geol. York., pi. x, fig. 1, 1836 ; and Dav., pi, iii, figs, 



7 — 10; pi. iv, figs. 3, 5 — 11 = faciger, Keyserling = fasciculata, 

 M'Coy. 



? 5. — CRASSA, De Koninck. An. Foss. de la Belgique, pi, xv bis, fig. 5, 1843 ; and Dav., pi. vi, 



figs. 20 — 22 ; pi. vii, figs. 1 — 3 =^ planicosta, M'Coy. 

 N.B. By some this shell is placed among the synonyms of Sp, duplicicostata, by 

 others among those of Sp. Lisulcata. 



6. — PLANATA, Phillips. Geol. of York., pi. x, fig. 3, 1836; and Dav., pi. vii, figs. 2.") — 36. 



17. — FUSiFORMis, Phillips, pi. ix, figs, 10, 11 ; Dav., pi. xiii, fig. 15. 



Of this only a single imperfect specimen has been discovered, so that the characters 

 and value of the species cannot be considered finally established. 



8. — TRIANGULARIS, Martin, sp. Pet. Derb., pi. xxxvi, fig. 2, 1809; and Dav., pi. v, figs. 



16 — 24 = ornithorhyncha, M'Coy. 



9. — TiUGONALis, Martin, sp. Pet. Derb., tab. xxxvi, fig. 1, 1809 ; and Dav., pi. v, figs. 



25—34. 



10. — BisuLCATA, Sow. M. C, tab. ccccxciv, figs. 1, 2, 1825 ; and Dav., pi. v, fig. 1 ; pi. vi, 



figs. 1 — 19 ; and pi. vii, fig. 4 = semicircularis, Phillips = calcarata, M'Coy 

 = transiens, M'Coy? 



11- — co-nv 01X1 k, Phillips. Geol. York., pi. ix, fig. 7, 1836; and Dav., pi. v, figs. 2 — 15 = 



rhomboidea, Phillips. 



12. — GRANDicosTATA, M'Coij. Brit. Pal. Fossils, pi. iii, D, fig. 29, 1855 ; and Dav., pi. v, figs, 



38, 39, and pi, vii, figs. 7—16. 



N.B. All these species are closely allied, and it may remain a question for further 

 consideration whether they should be all specifically separated. It is possible 

 that Sp. convolata may after all be nothing more than a very transverse and 

 V^ exceptional condition of Sp. bisulcata. 



13. — LAMINOSA, iH'Coy. Synopsis, pi. xxi, fig. 4, 1844; and Dav., pi. vii, figs. 17 — 22 = 



tricornis, De Koninck. 



