72 
JOURNAL OF THE GEOLOGICAL SOCIETY OF DUBLIN. 
limestone, there is a remarkable yellow vesicular sandstone, the 
true relations of which cannot at present be determined.”* I have 
no doubt this passage refers to the magnesian limestone of Tully- 
connel; and that through some mistake it has been called a “sand¬ 
stone;” or, perhaps its grittiness and a hasty examination of it may 
have given rise to the idea of this deposit being an arenaceous 
rock. That there is an error in the passage quoted appears evident; 
for in the Geological Map appended to Colonel Portlock’s “ Report,” 
the district of Tullyconnel is coloured pale-yellow, and marked 
“3 A 1,” signifying a calcareous rock associated with the carbo¬ 
niferous strata. Furthermore, the Colonel elsewhere refers to Tul¬ 
lyconnel as being a townland “ in which limestone may be pro¬ 
cured” for economical purposes, “ though at present obtained in other 
localities.”! I have every reason for supposing that this oversight 
or inadvertency has arisen in consequence of Colonel Portlock hav¬ 
ing been suddenly called on to close his Report, from his services 
being required in another quarter. 
The fossils from “ near Artrea,” in the Museum of Irish Indus¬ 
try, I have been informed, were collected by one of the officers 
assisting Colonel Portlock in his survey. 
The Tullyconnel magnesian limestone so closely resembles that 
with which I have been familiar from my very childhood, that I felt 
no difficulty whatever in recognising fragments of it in the old 
wall; and no sooner had I applied my hammer to them than several 
specimens of fossils, with which I was perfectly acquainted, lay 
before me. Having worked at the Zechstein fossils in the heart of 
Germany, and having made those occurring in Durham an especial 
study, my feelings may be imagined when I first saw their exact 
representatives in a district forming the almost westernmost boun¬ 
dary of Europe. 
As I was little more than an hour in the neighbourhood of Tul¬ 
lyconnel, doubtless all the species which occur there did not fall 
under my notice; but most of the specimens I collected are in such 
a state of preservation, that I have little doubt the determinations 
I have made of them will be found to be for the most part correct. 
On acquainting Professor Jukes with my discovery, heat once took 
a lively interest in it, and kindly forwarded to me for examination 
all the specimens in the Museum of Irish Industry. This has 
Op. cit., p. 588. 
f Op. cit., p. 674. 
