626 



MISS JANE DONALD ON CARBONIFEROUS 



It exhibits a slight variation, there being two fine lines on the part 

 of the whorl above the band. The angle is well developed on the 

 lower part of the whorl. Umbilicus distinct. Mouth broken. 

 Length 36 millim., width of body-whorl 19| millim. 

 Formation. Mountain Limestone. 



Murchisonia Yerneutliana, de Kon. (PI. XXI Y. figs. 6-8.) 



Murchisonia Verneuiliana, L. G. de Koninck, 1843, ' Precis 

 elem. de Geologie, par J". J. d'Omalius d'Halloy,' p. 516. 



Murchisonia Verneuiliana, L. G. de Koninck, 1843, ' Descr. des 

 Anim. Foss. du Terr. Carb. de la Belgique,' p. 414, pi. xxxviii. 

 fig. 5. 



Murchisonia Verneuiliana, PL G. Bronn, 1848, ' Index Palaeontol.' 

 p. 748. 



Is on Murchisonia Verneuiliana, var. Jcendalensis, F. M'Coy, 1855, 

 < Brit. Pal. Ptocks and Foss.' p. 532, pi. 3 h. figs. 11 and 12. 



Murchisonia Verneuiliana, L. G. de Koninck, 1877, ' Recherches 

 sur les Poss. Pal. de la Nouvelle-Galles du Sud,' p. 119, pi. xxiii. 

 fig. 15. 



Murchisonia Verneuiliana, J. J.Bigsby, 1878, 'Thesaurus Devonico- 

 Carboniferus/ p. 327. 



Murchisonia Verneuiliana, De Kon., 1883, ' Faune du Calc. Carb. 

 de la Belgique/ p. 25, pi. xxxiv. figs. 35, 36, 37. 



Shell conical, composed of from eight to ten angular whorls. A 

 little below the centre of each whorl there are two strong keels, 

 between which lies the sinual band ; the band is wide and sunk 

 between the two keels. The lines of growth are distinct, curving 

 back to the band above and coming forward again below ; on the 

 band they are arched, but not so strongly as in M. Jcendalensis, 

 M'Coy. The surface of the whorls is almost flat, being but slightly 

 convex. The base of the last whorl is convex ; it has a slight 

 angularity a little below the band, which is hidden by the suture 

 on the upper whorls. Prof, de Koninck says that the last whorl 

 has a tendency to become detached from the preceding whorls. 

 The sutures are deep. The mouth is a little longer than 

 wide. The columella is simple, and there is no umbilicus. 

 The surface of the whorls is generally ornamented with fine spiral 

 striae. The largest of the specimens in the Woodwardian Museum 

 has these spiral lines well preserved. Another only shows two 

 of the strongest lines above the band and two below ; the keels 

 bounding the band of this specimen also appear to be slightly 

 undulating, but this may arise from wear, as the surface of the shell 

 is much worn. The specimen figured by de Koninck has only the 

 spiral lines below the band. 



De Koninck says that this shell differs from M. plicata, Goldf., 

 by the depth of its suture and also by the absence of the keel on 

 the base. In the type of M. plicata, Goldf., which I have examined 

 in the Bonn Museum, there is a still greater difference, for the upper 

 margin of the whorl is nodulose at the suture, the keel below the 



