168 WILLIAM HELLIER BAtLy 
Two other fossil localities, also in Silurian strata, have 
been observed more inland, one of them being a little south of 
Stamullin, close to the river Delvin, where a Crinoid head, doubt- 
fully referred to Glyptocrinus, and single-celled Graptolites— 
probably G. Hisingeri—were long since obtained by the Geo- 
logical Survey Collectors, from grey shales and grits. The other 
is situated about a mile and a-half west of Balbriggan, at an old 
quarry on the road to Balscaddan, where similar grey shales 
yielded a few fossils, amongst them Orthis calligramma and 
Theca triangular, * 
Lower Siivurian fossils ; near Balbriggan, Co. Dublin. 
Hyproz0a: Graptolites. 
**Diplograpsus pristis. 
***Graptolithus Hisingeri. 
if tenuis. 
¢ 
AcTINozoA: Corals. 
**Tavosites fibrosus. 
Motxusoa : Brachiopoda. 
Crania ! 
**Lepteena sericea. 
Orthis Actonie. 
=) ye calligramimna. 
* 5). porcata. 
*Strophomena alternata. 
* " deltoidea. 
Pterogpoda. 
Theca triangularis. 
ECHINODERMATA. 
Crinoid fragments. 
Glyptocrinus ? 
Crustacea: Phyllopoda. 
Beyrichia, species undetermined. 
Trilobita. 
Calymene brevicapitata. 
Cybele verrucosa. 
CARBONIFEROUS LIMESTONE is the prevailing formation in the 
immediate neighbourhood of Dublin, and although for the most 
part covered by drift, is observable at the numerous quarries 
opened for economical purposes, at coast sections, and Railway 
cuttings. 
Sections of this formation are to be seen on the south of 
* Explanation of Sheets 91 and 92, Geological Survey of Ireland, p. 21. 
