48 Messrs. Jones and Kirkby on Carboniferous Entomostraca. 
and lower boundaries, being in some places wholly “ Carboni- 
ferous,” at others wholly made up of “ Old Red,” and elsewhere 
combining portions of each ; and they restrict the term to the 
upper portion of the Old Red Sandstone series, distinctly below 
the beds with marine fossils. They consider that the “ Carboni- 
ferous Slate”? (about 150 feet thick), below the “ Carboniferous 
Limestone” (3000 feet), in the north-eastern districts, is the 
same as the “ Lower Limestone Shales” of England, and that 
the “ Carboniferous Limestone” thins away on the south-west 
and is wholly replaced by the ‘ Lower Limestone Shales” 
(about 5000 feet), which are there cleaved, and therefore known 
as “Carboniferous Slate.” The latter, in consequence, are in 
the south-west the equivalents of the “Carboniferous Lime- 
stone” and “ Lower Limestone Shales” together in the north- 
east. 
As this arrangement simplifies the order and succession of 
the “ Lower Carboniferous” strata, we use both nomenclatures 
in the annexed table of the Entomostraca that we have observed 
in Sir R. Griffith’s specimens. 
We have also seen other Carboniferous Entomostraca from 
Ireland, which have been kindly submitted to us by the Officers 
of the Geological Survey of Ireland. 
I. From the “ Carboniferous Limestone.” 
1. Meath (Map, Sheet 33/4); Clonalvy, near Naul. Entomo- 
conchus Scouleri. 
2. Meath (Sheet 27/1); Duleek. Light-grey limestone. 
Cypridina primeva (gregarious). 
3. Dublin (Sheet 7/1); Oldtown. Leperditia Okeni. 
4, Tipperary (20/2) ; Carrig-Church, about 24 miles north- 
west of Nenagh. Dark-coloured Polyzoan Limestone, with 
Echinoderm fragments and Shells. Leperditia subrecta. 
5. Limerick (Sheet 11/2); Ballynolan, near Pallaskenry. 
Entomoconchus Scouleri. 
6. Limerick (10/4); Glenbane, near Askeaton (No. 4253 a). 
Leperditia Okent. 
7. Limerick (29/1); Rathkeale. Grey limestone with Fenes- 
tella. Leperditia subrecta. 
8. Cork (76/3); Ballyvodock, about 2 miles south-west of 
Middleton. Grey fossiliferous limestone. Entomoconchus Scou- 
lert (gregarious). 
II. “Lower Limestone Shale.” 
1. Londonderry ; Ballrascreen. Hard dark-grey shale, mica- 
eeous, full of small Leperditia. (Portlock’s Collection.) £. sub- 
recta, L. Scotoburdigalensis, and still smaller obscure forms. 
