12 CARBONICOLA, ANTHRACOMYA, AND NAIADITES. 
§ II. CRITICAL BIBLIOGRAPHY. 
The literature of this subject, though scattered, is fairly extensive; but 
unfortunately authors have worked independently, and not consulted previous 
writings: and this fault is much more marked amongst the Continental 
paleontologists, some of whom, writing within the last thirty years, have ignored 
all the work done in Great Britain; and, failing to grasp the number of varietal 
forms which the shells under notice are capable of assuming, have described each 
small variation as typical of a different species. 
1720. 'The earliest literary trace of these Coal-measure shells that I am able to 
discover goes back as far as 1720, in a work entitled ‘Memorabilia Saxioniz 
Subterraniz,” by G. F. Myles, published at Leipzig, a work of high artistic and 
paleontographical value in the accuracy and detail of its many plates of fossil 
plants and prehistoric remains. Only one plate, however, refers to the subject of 
the present memoir, pl. xxvi, figs. 1, 9, 10, with a short description at p. 39, 
which [here transcribe. The quaint mingling of Latinand German, and reference 
to the Unio-like character of the fossils, are of interest : 
Fig. 1. ‘‘ Patellee seu conche pictoriz werden darum die auf diesen Stein sie 
preesenterenden Muschelen genennt, weil sie der Mahler gar sehn zu gebrauchen 
pflegen, daher sie auch in L. 17, ff. de instr. et instrum. leg. als instrumenta 
pictorum angeschen werden. Nicht weniger finden sich auf diesen Stein noch 
eine Art, welche Dactyli, germ. Kinel-Nagel, oder Finger-Muscheln und Schalen 
heissen, deren Plinius, Lib. 9, cap. 61, gedenckt.” 
Fig. 8. ‘* Die Muschel so allhier sich zeiget, ist gleichfals mt dem sub. fig. 1, 
erwehnten Dactylis zu vergleichen immassen auch die Selb.” 
Fig. 10. ‘‘ In copia communicerten denen Patellis f. conchis pictoris, obschon 
nicht in dergleichen Grosse, iiber einkommen.” 
The former two figures refer to Carbonicola, the latter evidently to Naiadites. 
It is interesting to note in this earliest account the occurrence of these two 
genera together, and the reference of these fossils to Unio. It will be seen that 
the older writers on this subject were all of this opinion, and many Continental 
authors have continued to hold this view. 
1793. From 1720 to 1793 I can find no mention of Coal-measure shells; but 
in that year the Rev. David Ure published his ‘ Natural History of Rutherglen,’ 
a lasting testimony to his acuteness of observation and scientific mind. He 
describes certainly one shell now referred to Carbonicola, and possibly four. He 
says, p. 311, ‘The marble in Rutherglen . . . abounds in mussels. 
Some entire specimens are enveloped in till” (? marl). He figures a specimen, 
pl. xvi, fig. 4, which has the appearance of the Carbonicola aquilina of later authors ; 
