ANTHRACOMYA WARDI. 107 
specimen from the Collection of Mr. George Wild, fig. 18, show what I take to be 
younger forms of the same species, the general shape of the shell being the 
same, but young forms have a sharper oblique ridge and radiating lines on the 
posterior slope of the shell above the oblique ridge. The typical blunt, truncate 
posterior end, smuous above, is common to both the young and adult state. 
M. d@’Kichwald’s figure of Modiolopsis tenera differs from Anthracomya Wardi in 
being shorter, whilst no mention is made of the oblique compression and blunt 
ridge, though the outline of the posterior border is very similar. 
The specimen from the Holly Lane Shale at Whitfield (Pl. XV, fig. 20) possesses 
the characters of the young shells. The study of a series has convinced me that 
the shell that I described in 1893 (op. cit. supra) as Anthracomya angusta is only 
a very young specimen of A. Wardi. I refigure this specimen on Pl. XV, fig. 12; 
and, from a closer examination of the matrix, doubt its having come from the 
Hard-mine bed, several shell-bearing beds being mixed on the tip heap where I met 
with the specimen. I have figured on Pl. XIII, figs. 13, 15, and 16, two shells 
from the coal shale of Wakefield, which I take to belong to this species. The 
extreme posterior end has not been preserved; but if one may judge from the 
direction which the lines of growth take in the posterior part of the shell, it 
would correspond with that possessed by the type. It is possible that they may, 
in the future, when more specimens are obtained, be shown to be distinct. 
Pl. XIII, fig. 15, I have with hesitation referred to this species; it is from the 
roof of the 8-foot coal in the coal-measures of Durie, Fife, and was given me by 
Mr. Kirkby, of Leven. It has a certain resemblance to the shell from Wakefield, 
but it is unlike every other example in having that portion of the shell above the 
oblique ridge evenly gibbous. There are, however, in this place obscure radiating 
- lines, and the posterior end, not quite perfect, was hardly so truncate as in the 
type; but on comparing this figure with that of fig. 19, Pl. XV, a close resem- 
blance will be noted. 
There is a fairly typical specimen of this species in the Geological Survey 
Collection from Burrs, near Bury, Lanes, labelled Sanguwinolites, sp., in Mr. Salter’s 
handwriting. It is in quite a different matrix from the specimens labelled 
Anthracomya sanguinolaris (MS.), and referred to at p. 35 of the ‘ Memoir of 
Geol. Surv.,’ “The Geology of the Country round Bolton-le-Moors,” which I 
identify as A. Williamsoni. 
I noted a specimen in the museum at Dresden from the Grube Hannibal, near 
Bochum, which I believe to belong to this species. In Great Britain Anthracomya 
Wardi is rare, even in the beds in which it does occur, and has a very limited 
horizontal distribution. 
