26 CARBONICOLA, ANTHRACOMYA, AND NAIADITES. 
Naiadites (Anthracoptera) carbonaria, Dawson. Naiadites ovalis, Dawson. 
= iy levis, Dawson. _ angulata, Dawson. 
a (Anthracomya) elongata, Dawson. 3 obtusa, Dawson. 
x arenacea, Dawson. Anthracosia Bradorica, Dawson (p. 314). 
I have, by the kindness of Sir W. J. Dawson, been allowed to examine a 
series of his specimens, and the result appeared in a joint paper before the 
Geological Society of London (read February 21st, 1894), ‘Quart. Journ. Geol. 
Soe.,’ vol. L, pp. 435—442, 1894. 
1861. In 1861 appeared the first edition of Hull’s ‘ Coal-fields of Great 
Britain,’ which contained one plate, of which fig. 1 is said to be Anthracosia 
robusta ; and in a very brief reference to the Mollusca, pp. 40 and 48, under the 
names Anthracosia (Unio of early authors) and Modiola, afew words are said as to 
the marine or brackish water habitat of these forms. 
In later editions, 1873 and 1881, the original plate was done away with and a 
new one (to face p. 38) given, with Anthracomya carinata (sic, for Anthracoptera 
carinata), Anthracosia centralis, and A. aquilina. 
Prof. Hull’s views as to the habitat of these shells appears to have somewhat 
changed ; he says, ** Anthracosia (Unio), Anthracomya, and Anthracoptera, capable 
apparently of living in fresh-water lakes or brackish water estuaries.” 
A very valuable paper by the same author, bearing very little on the shells 
themselves, from which I have quoted freely above (pp. 2, 3), appeared in the 
‘Quart. Journ. Geol. Soc.,’ vol. xxxiii, 1877, p. 613, &c., “On the Classification 
of the Carboniferous Series;” but I doubt whether any evidence which he has 
adduced on the strength of the shells in question is of much value, owing to the 
great confusion which has existed up to the present time with various authors as 
to the generic characters of the various forms. 
1856-63. The first memoir of Mr. Salter which I can find on this subject, to 
which he paid some attention, appeared in 1860 as the “ Memoir of the Geological 
Survey,” ‘The Iron Ores of Great Britain,’ Part I, 1856. ‘The Iron Ores of 
the North and North Midland Counties’ contains only the casual remark 
that certain beds at Chesterfield (‘“‘dog-tooth rake’’) ‘are almost made up 
of fossil bivalves (Anthracosia),” which he refers to Unio agrestis of Brown. 
He says that the “ Wallis rake” at Codnor Park, Butterley, is full of the same 
shell. 
1861. In Part III, ‘The Iron Ores of South Wales,’ in 1861, he enters more 
fully into the subject, and gives the diagnosis of his new genus Antlracomya, 
describing and figuring— 
Anthracomya Adamsii. Anthracomya subcentralis. 
A pumila. a senen. 
