104 CARBONIFEROUS LAMELLIBRANCHIATA. 



tliis reason M'Coy did not recognise that his Pecten elongatus belonged to Phillips's 

 species. The shell in the Gilbertson Collection labelled P. elongatus (PI. XX, 

 fig. 14) can hardly have been the figured specimen, as it is so much smaller than 

 the figure, but both figure and specimen are left valves. Both Phillips's and 

 M'Coy's specimens are so smooth that I think it likely they were casts. De 

 Koninck adopted M'Coy's name, and does not appear to have considered that 

 Phillips's shell occurred in Belgium. 



After examination of the types in the Science and Art Museum, Dublin, I 

 cannot but refer P. depilis, M'Coy, to Phillips's species. It is a smaller shell, but 

 the contour of the valve and general shape show its close affinity to P. ellypticu/m. 

 I think P. jilatus of the same author also belongs to Phillips's species. I am unable 

 to identify the radiating lines, as shown in the enlarged figure, in the specimen 

 which is now considered to be the type. It is not P. anisotum, for the ears are not 

 ribbed, but are plain. 



Pseudamusium anisotum, Phillips, sp., 183G. Plate XXI, figs. 1:3 — 20. 



Pecten anisotus, Phillips, 1836. Geol. Yorks., pt. li, p. 212, pi. vi, fig. 22. 



consimilis, M'Coy, 1844. Synops. Carb. Foss. Ireland, p. 91, pi. xv, 



fig. 16. 

 variabilis, M'Coy, 1844. Ibid., p. 101, pi. xvi, fig. 7. 

 Lima obliqua, M'Coy, 1844. Ibid., p. 88, pi. xv, fig. 7. 

 cf. Pecten sibeeicus, de Verneuil, 1845. Geol. Eussie de l'Europe, p. 329, pi. xxi, 



fig. 7. 

 — anisotus, Brown, 1849. Illust. Foss. Conch., p. 156, pi. lxv, fig. 24. 

 Aviculopecten anisotus, Morris, 1854. Cat. Brit. Foss., 2nd ed., p. 164. 



de KonincJc, 1885. Ann. Mus. Roy. d'Hist. Nat. Belg., 

 torn, xi, p. 237, pi. xxxix, fig. 22. 

 cf. Steeblopteeia Renaedi, de Koninck, 1885. Ibid , p. 203, pi. xxxiv, fig. 27. 



Specific Characters. — Shell below medium size, almost equivalve, inequilateral, 

 obliquely rotundato-ovate, only moderately convex. The margin continuously 

 convex from ear to ear, more so in front, where the anterior border is produced. 

 The hinge-line straight and short. The umbones small, triangular, pointed, 

 flattened, slightly raised, placed about the centre of the hinge-line, but posterior to 

 the median vertical diameter of the valve. The anterior and upper part of the 

 valve much cut away for the byssal notch, and the border extending forwards 

 considerably beyond the anterior ear. The anterior ears well marked, depressed, 

 well defined from the valve, separated in the right by a slit for the byssns; the 

 posterior cars wry small, triangular, compressed, the posterior superior angle very 

 obtuse. Shell very thin. 



