32 CARBONICOLA, ANTHRACOMYA, AND NAIADITES. 
The notes of interrogation and remarks are my own, from a personal examination 
of the specimens figured. 
One new form, “ Anthracomya Wardi,” is described by R. Etheridge, sen., as if 
that genus belonged to the Myacide. In the text which deals with the strati- 
graphy of the coal-field, the beds in which the various forms occur are carefully 
noted. 
1878. Mr. G. H. Kinahan, M.R.I.A., gives in his ‘ Geology of Ireland’ a 
plate (pl. iv) with two forms of Coal-measure bivalves from Bilboa, Queen’s Co., 
which he names Myacites fabeformis and Anthracosia Bilboensis. I have seen 
examples of the latter in the Royal Museum, Dresden, which were collected from 
Bilboa by Dr. Geinitz, and which I recognise as Anthracomya Williamsoni (Brown). 
He quotes Mr. Baily as to the occurrence of bivalve mollusca in the various 
Trish coal-fields. 
1880. In 1880 Dr. John Young read, January 13th, a paper, subsequently pub- 
lished in the ‘ Transactions of the Geological Society of Glasgow,’ vol. vi, p. 223, 
for that year, entitled ‘*‘ Notes on some Carboniferous Lamellibranchs.” He dis- 
cusses and sums up in favour of the fresh-water habitat of the genera Anthracoptera, 
Anthracomya, and Anthracosia. He there chronicles his discovery of prismatic 
cellular structure in the shells of Anthracoptera (Naiadites). 
1880. In the ‘ Paleeontographica,’ vol. xxvii, p. 109, is a paper by Dr. Hans 
Polig, under the curious title “‘ Maritime Unionen.”’ In this he advances the view 
that the Anthracosie of the Coal-measures, the Unios of the Triassic, and the 
Cardiniz of the Jurassic form a natural group, connecting on the one hand the 
OCyprinide, and on the other Wajades. 
1880-83. *‘ The Niederrheinisch Westfillisch Steinkohlen-Gebirge Atlas’ was 
published by Achepol during the years 1880 to 1883. This remarkable work is 
distinguished by having, instead of plates, photographs of the objects themselves. 
These photographs are often so imperfect, from bad arrangement of the light during 
the process of photography, and the objects themselves are so often fragmentary 
and indistinct, that little or nothing can be made out of them. Added to this, the 
inventive genius of the author as to species-making is excessive, and he describes and 
ficures thirty-seven forms, thirty-two of which are said to be new, although he has 
adopted names which previous authors had given to different forms. 
Anthracosia Goldfussi, Achepol. Anthracomya Williamsoni. 
“i tellinaria. 
” securiformis, Ludwig. 

1 Since going to press I have by the courtesy of the Officers of the Geological Survey of Ireland 
been permitted to examine the specimens in the Dublin Museum. I consider that the forms labelled 
there as above are both of them Anthracomya closely allied to A. Williamsoni. 
