468 



THE GEOLOGIST. 



17. „ EEEDii, Dav., pi. v., fig. 40-47. 



Ig* TKiKADiALis, PMllips, Geol. York, pi. x.,fig 7: and Dav., pi. ix,, 



fig. 4 — 12. = trisidcosa and sexradiales, Phillips. 



19. piNGUis, Sow., M.C., tab. cclxxi., 1820: and Dav., pi. x., fig. 



1 — 12 = rotundaia, Sow. (not Martin) = subrotundata, 

 M'Coy. I should have preferred adopting Sowerby'a 

 name, rotundata, for the species ; but, as that name had 

 already been employed for another species, I felt com- 

 pelled to adopt that of jmiguis for the species. The form 

 rotundatus is the normal condition of the species ; the var. 

 pinguis is composed of shells that have been either stinted 

 in their development, or are monstruosities. 



20. „ ovALis, Phillips, Qeol. of York, pi. x., fi_g 5; and Dav., pi. ix., 



figs. 20 — 26 = ezarata, Fleming (?) hemisphcerica, 

 M'Coy. 



21. „ iNTEQ-EicosTA, Phillips, Geol. of York, pi. x.,fig. 2 : Dav., pi. ix., 



figs. IS — 191 = rotundata, Martin 1=paucicostata ? M'Coy. 



N.B. — The species composing this little group are all 

 very nearly connected, indeed, it is at times very difficult 

 to distinguish some of the varieties of the three last 

 named one from another, although the generality of 

 specimens appear to be tolerably distinct. 

 '22. „ EHOMBOiDALis, M'Coy, Synopsis, pi. xxii., fig. 11, 1844 : and 

 Dav., pi. xii., fig. 6, 7. 



23. „ GLABEA, Martin, Pet. Derb., pi. xlviii., 9, 10, 1809 : and Dav., 



pL xi., figs. 1 — 9, and pi. xii., fig. 1 — 5 = obtusa s^nd 

 oblata, Sow. = linguifera, symmetrica, and decora, Phillips. 

 The varieties presented by this species are endless, so 

 that one can hardly discover a single permanent dis- 

 tinguishing character. 



24. „ TJEii, Fleming, Brit. Animals, p. 376, 1828 : and Dav., pi. xii., 



fig. 13, 14. 



„ OAELTTKiEXSis, Dav. pi. xiii., fig. 14, 1857. 

 ' 26. „ LLNEATA, Martin, Pet. Derb. tab. xxxvi., fig. 3, 1809 : and Dav., 

 pi. xiii., fig. 1 — 13. = imbricata, Sow. =. reticulata, 

 M'Coy = elliptica and mesoloha, Phillips. Some authors 

 consider Sp. eliipiica SiTidSp. lineata as specifically distinct. 



27. Spiripeeina ceistata, Schl. var octoplicata, Sow., M.C., tab. Ixii., fig. 



2-4, 1827 : Dav., pi. vii., figs. 37-47. 



28. ? INSCULPTA, Phillips, Geol. York, pi. ix., fig. 2, 3, 1836 : Dav., pi. 



vii., fig. 48, 55 = crispa, De Koninck (not of Linnseus) 

 = quinqueloba, M'Coy. 

 ? 29. ? MINIMA, Sowerby, M.C., tab. ccclxxvii;, fig. 1, 1822 : and Dav., 

 pi. vii., figs. 56 — 59. I have never seen more than 

 Sowerby's own two examples of this shell, and I consider 

 it to be an uncertain species, as well as the Sp. partita of 

 Portlock, which is probably nothing more than a synonym 

 of one of those above-mentioned. 



30. Cyetina SEPTOSA, Phillips, Geol. of York, pi. xi., fig. 7, 1836 : Dav., pl.xiv., 



fig. 1 — 10, and pi. XV., fig. 1, 2. This is a very in- 

 terestiDg species, but rarely found with the two valves 

 united. Some of the interior details of the smaller 

 valve are still unknown. 



31. „ doesata, M'Coy, Synopsis, pi. xxii , fig. 14, 1844 : and Dav., pi. 



XV., fig. 3, 4. I consider this to be among the uncertain 

 species, only two or three imperfect specimens having 

 been hitherto discovered. 



32. CAEBONAEiA, M'Coy, British Palaeozoic Fossils, pi. iii., d., fig. 



12-18, 1855: and Dav., pi. xv., fig. 5-14. 



