310 
SUPPLEMENT TO THE EPvlTISPI 
scientific public by Mr. Neilson, in a paper entitled " Geological Notes on the Cuttings 
in the City of Glasgow Union Railway, between Bellgrove and Springburn " (' Trans. 
Geol. Soc. of Glasgow,' May 18th, 1875). The author says in his paper that "it would 
be interesting to know the mineral character of the specimen in the Jermyn Street 
Museum, as we could thereby fix with tolerable certainty if this be the bed from which it 
came. It would be curious if this should now prove to be the case, and that it should 
not have been decided for twenty years after the publication of Mr. Davidson's Mono- 
graphs ; P. pustulosus, Phillips, which had not at that time been got in Scotland, is 
figured from the same locality ; and we also find in this bed specimens which would have 
been referred to this species but that there were found all varieties between it and the 
typical P. scabricidus, Martin, to which they have been referred, although some of the 
specimens show the median ridge of the dorsal valve to be simple, as in P. pustulosus" 
I have, thanks to the kindness of Mr. Etheridge, compared the specimen and its 
matrix I had described in my Monograph with Mr. Neilson's examples from Garngad, 
and found them to agree in every particular. Among Mr. Neilson's specimens I found 
internal casts of both valves, on which the muscular scars and reniform impressions are 
well defined (Sup., PI. XXXVI, fig. 8). We consequently now know the strati- 
graphical position and locality from whence the Scottish specimens of Prod, carhonarius 
have been obtained. In the same locality, and at the same stratigraphical horizon, Mr. 
Neilson collected several specimens of Productus sinuatus, de Koninck, Productus 
mm'icatus, and a curious variety of Athyris amhigua, with mesial fold greatly produced. 
41. Productus tessellatus, de Konwch. Dav., Carb. Mon., p. 165, PI. XXXITI, 
figs. 24, 25 ; and PI. XXXIV, fig. 14 ; 
Sup., PI. XXXVI, figs. 3, 4, 5. 
Subsequent to the publication of my description and illustrations of this elegant 
species Mr. Joseph Wright has obtained from the Carboniferous Limestone of Little 
Island, Cork, several specimens showing two fringes quite perfect, and he is inclined to 
think that in fringed Producti, as well as in Athyris, each line of the shell-growth had 
its fringe, and that three of his specimens would confirm that view, at any rate with 
respect to P. tessellatus. The singular manner in which these fringes are curved and 
bent upon themselves, and crumpled up as it Avere, on three individuals, leads him to 
suspect that they may have been of a very delicate membranous nature. 
Along with this species, and in the same locality, Mr. J. Wright has found examples 
of Prod. Youngianus, Betzia radialis, B. idotrix, Bhynchonella trilatera, Bhyn. refexa^ 
Athyris expansa (near Cork), species that will require to be added to the list of Irish 
Carboniferous Bracliiopoda. 
