176 CARBONICOLA, ANTHRACOMYA, AND NAIADITES. — 
the characteristic form of the anterior end and the subparallel margins appear to 
me to be typical of A. Wardi. 
Dr. Young tells me that these are the only shells of this species known from 
this locality, and that he has not met with this form before. I have no hesitation 
in referring them to the genus Anthracomya, and to the same species as figs. 13 
and 15 of Pl. XIII, although the Possil shells are so much finer than any others. 
Conditions must have been extremely suitable for the growth and development of 
the shell in this locality, and it is remarkable that no more specimens are to be 
met with in Scottish collections. Dr. Young informs me that crushed forms of 
Naiadites, probably N. modiolaris, occur with this shell, and that Lingula squanu- 
formis also is found in bands of black shale in connection with the Possil Lower Iron- 
stone, but that Naiadites and Lingula never occur in exactly the same stratum. 
Of Dr. Young’s two specimens one is very much larger than the other. The 
finer example (Pl. XXI, fig. 9) is, however, somewhat crushed and imperfect at 
the anterior end, and does not show the typical form of the shell so well as the 
other (Pl. XXI, fig. 10). 
This shell measures— 
Antero-posteriorly : : : . 66 mm. 
Dorso-ventrally at umbo , : ssa), 
Laterally . tl Oee ss 
Anthracomya Phillipsii (p. 120).—Pl. XXI, fig. 7, is a non-compressed 
example of this species from the Upper Coal-measure shales, Speedwell Pit of the 
Gloucestershire Coal-field. Typical compressed examples occur in the same 
shales. 
Anthracomya dolobrata has also been obtained from the Lancashire Coal-field ; 
two specimens, of which I figure one, fig. 13, are assuredly young. 
16. ANTHRACOMYA SUBPARALLELA, Portlock, sp., 1843. Plate XVII, figs. 1 and 2; 
Plate XXI, figs. 2—6. 
Mop10La sUBPARALLELA, Portlock, 1843. Report Geology County London- 
derry, &e., p. 433, pl. xxxiv, fig. 16. 
= —_ Morris, 1848. Catalogue of British Fossils, p. 92. 
? CARDINIA SUBPARALLELA, Keyserling, 1846. Petschora Land, p. 255, Pleeexe 
fig. 15. 
— d’ Orbigny, 1850. Prodrome de Paléontologie, p. 131. 
= _ Hichwald, 1860. Lethzea Rossica, 2nd part, p. 1007. 
Moprora Macapamu, Baily, 1875. Figures of Characteristic British Fossils, 
p. 114, pl. xxxix, fig. 6. 
