320) MISS DONALD ON PROTEROZOIC GASTEROPODA [ May 1902, © 
collection of Mrs. Gray. She has now six others, one of which 
shows the lines of growth distinctly, and is figured in Pl. VII, 
fig. 11. 
Ss 
I am greatly indebted for the loan of specimens to Mrs. Robert 
Gray, Edinburgh ; Prof. Hughes, Cambridge ; Prof. Sollas, Oxford : 
the late Prof. Lindstrom, Stockholm; the Geological Survey of 
Scotland; and the respective committees of the Museums at Carlisle, 
Bristol, and Cardiff. I must also render thanks for assistance in 
studying collections to Mr. E. T. Newton, Dr. A. Smith Woodward, 
Mr. R. B. Newton, Mr. H. A. Allen, Mr. Madeley of Dudley, and 
Dr. Scharff of Dublin; and for help in looking up references to 
Mr. C. D. Sherborn. To Mr. Goodchild 1 am much obliged for 
revising this paper. 
Family Murcutsonitipm, Koken. 
Genus Murchisonia, @’ Arch. & de Vern. 
Morcuisonia (?) DUDLEYENSIS, sp. nov. (PI. VII, fig. 1.) 
Diagnosis.—Shell somewhat robust, elongated, turreted, com- 
posed of more than nine whorls. Whorls increasing gradually, 
strongly angular below the middle of the earlier whorls and 
rather above the middle of the body-whorl, flattened. or slightly 
concave above, convex below. Angle surmounted by a broad, flat 
band, which represents the slit or sinus in the outer lip. Lines of 
growth imperfectly seen, sloping forward below the band at a 
moderate angle. Aperture unknown. Surface apparently smooth. 
Remarks and Resemblances.—This species, so far as I know, 
is represented only by two external moulds. In its robust form 
and broad prominent band it recalls the Carboniferous species 
M. kendalensis, M‘Coy ; also some of the smooth varieties of the type 
M.sturbinata, Schloth., especially where the band of the latter is so 
worn as not to show its grooved form limited on each side by a strong 
keel. As the species under discussion is not very well preserved, it 
is possible that the band may also have been originally bounded by 
keels in the earlier stages of growth, as in M. kendalensis—if not 
in every stage, asin M. turbinata. Taking this into consideration, I 
refer it to Murchisonia, though the aperture and lines of growth are 
not sufficiently preserved to show whether it possessed a true slit 
in the outer lip. Among Silurian species it most nearly resembles 
M. attenuata, His., but differs in having the band situated lower 
on the whorl, the sutures not so oblique, and the lines of growth 
sloping less strongly forward below the band. 
Localities and Horizon.-—The largest specimen is in the 
Dudley Museum, and is from shale between two divisions of the 
Wenlock Limestone, Dudley. The apex is imperfect, and the 
nine existing whorls measure 56 millimetres in length and 19 mm. 
in width. The other and better preserved example is in the Museum 
of Practical Geology, London, and is figured in Pl. VII, fig. 1. It 
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