MURCHISONIA. 
311 
In the British Museum is a specimen which is supposed to be Sowerby's type 
of his B. spinosum from Bradley. It evidently belongs to this species, as an 
interesting variety, and may be compared with PI. XXIX, figs. 9 and 10, but 
differs in its nodules, which are fewer and more defined. The matrix is very like 
that of the Chudleigh shells, but the material of the shell itself is crystalline. I 
could well imagine that it came from Chudleigh. 
The originals of two of Phillips's figures (192 h and c) of M. sjnnosa are in the 
Museum of Practical Geology ; one of these belongs to the group curta, the 
other is intermediate between curta and spinosa. 
The specimen described by Phillips as MurcMsonia geminata is in the Museum 
of Practical Geology, and a comparison of it with other specimens proves it to be 
only a variety of the present shell with more angulated whorls and more numer- 
ous and finer nodules than usual. It would lie between the groups intermedia 
and angulata. 
M. tricinda, Mtlnster,^ agrees with some of our examples, and evidently must 
be referred to the same species (cf. PI. XXX, fig. 11). It is a very imperfect 
example of a young shell. 
M. Hercynica, F. A. Romer, seems only to differ from some of our smooth 
varieties by having somewhat more pronounced spiral ridges. In Homer's figure 
these seem indistinct, and not very different from what is seen in some of the 
English shells (cf. PI. XXX, fig. 6), and, therefore, are probably not of specific 
value. Clarke regards M. conula, de Koninck,^ as possibly identical with it, but 
that shell is certainly different from M. turhinata. 
In the Battersby Collection of the Torquay Museum is a badly preserved shell 
which is just like Pleurotomaria nerinsea, Sandberger. This is much more elongate 
than usual, but not quite as much so as is Sandberger's figure. The only mark- 
ings seen are two foliaceous ridges, bounding a wide sinus-band, which is situated 
rather low on the whorl. This specimen is certainly a variety of M. turhinata, 
and hence it follows that Sandberger's type must also belong to it, and, therefore, 
his name becomes a synonym. 
In the same Museum are three small specimens which exactly agree with one 
of the figures given by Sandberger of his Fl. angulata. They appear to be small 
forms of our group angulata, and hence are connected by Mr. Yicary's shell 
(PI. XXX, fig. 12) with the group intermedia. Sandberger identifies his shell with 
M. angulata, Phillips, of the Pal. Foss. ; but not with his Bostellaria angulata,^ of 
the Geol. of Yorkshire. A comparison of these two figures and of that given by 
de Koninck in his ' Desc. Anim. Foss.' certainly gives every reason for regarding the 
Carboniferous species as distinct. The second or shorter of Sandberger's two 
1 1883, de Koninck, ' Ann. Mus. Eoy. H. N. Belg.,' vol. viii, pt. 4, p. 17, pi. xxxiv, figs. 9, 10. 
2 1836, Phillips, ' Geol. Torks.,' vol. ii, p. 230, pi. xvi, fig. 16. 
