On the Occurrence of Crystals of Salt im Chert. 131 
As I have found examples of these crystals in the chert sections 
taken from places in Kilkenny at the extreme 8.E., and Fermanagh 
and Sligo on the extreme N.W., of the central plain, it may 
fairly be assumed that they are widely distributed wherever the 
chert-beds of the upper Carboniferous Limestone are to be found. 
Whether they may not also be found in the limestone itself is a 
point which as yet I have had no opportunity of determining. 
I now proceed to state some of the instances referred to. 
1. Co. Kilkenny, Bonnet’s Rath Quarry. White laminated chert 
with organic structure, containing clear colourless cubes of sodium 
chloride in large numbers and very minute, together with some 
rhombic crystals of calcite. (2. Specimens from same quarry.) 
3. Co. Kilkenny, Kilmagar. Dark chert with laminated struc- 
ture, taken just below the Yoredale shales. Cubes with darkened 
sides and translucent centres. Mr. Hardman’s analysis (No. XI.) 
indicates the presence of sodium in this rock. 
4. Co. Fermanagh, Benachlan, above Florence Court. Grey 
chert with organic structure. Contains great numbers of very 
small cubical crystals, clear and colourless. 
5. Co. Sligo, Ballymote. Banded chert with organic structure. 
Numerous clear and colourless very small cubes; others with 
darkened sides (see Figs. 1, 2). 
Fig. 2. 
From another portion of the same section. 
Mr. Hardman’s analysis (No. I) indicates the presence of sodium. 
