1869.] 



BAILY IRISH GRAPTOLITES. 



159 



numerous specimens examined in connexion with my duties on the 

 Geological Survey of that country. 



Commencing with the south of Ireland, the first place to be 

 noticed is in the county of Waterford, on the banks of a stream 

 called the Dalligan river, five miles N.E. of Dungarvan, where 

 dark grey argillaceous shales occur full of the small diverging 

 Graptolite, Didymograpsus sextans, Hall ; they were first discovered 

 at this place by Mr. Charles Galvan, of the Geological Survey. In 

 the list of fossils, appendix to * Siluria,' 1867, the geological range of 

 this species is limited to the Llandeilo group of rocks. Proceeding 

 towards the city of Waterford, at Lady Elizabeth's Cove, in Tramore 

 Bay, highly inclined black slates dipping 80° N.E. may be seen on 

 the shore just below high- water mark, penetrated by a greenstone 

 dyke and in close proximity to rocks containing a profusion of fossils 

 of Caradoc-Bala age ; these slates are of a dull earthy character, 

 much impregnated with pyrites, and yielded the following species : — 



Graptolithus Hisingeri, Carruthers ( = 



Sagittarius). 

 ♦Didymograpsus sextans, Hall. 

 CJadograpsus gracilis, Hall. 



together with the following reticulated and many-branching forms, 

 the affinities of which to Graptolites I agree with Mr. Carruthers in 

 considering to be very doubtful, — 



Diplograpsus pristis, Hisinger. 

 Climacograpsus bicornis, Hall. 

 Dicranograpsus ramosus, Hall. 



Dictyonema, sp. 



Callograpsus elegans or Salteri. 



Dendrograpsus flexuosus or diffusus. 



At a second locality, in Tramore Bay, Diplograpsus pristis occurred 

 in grey slate, associated wdth Trilobites. 



A little north-Avest of the town of Waterford, on the left bank of the 

 river Suir, are cliffs 150 feet in height, composed for the most part 

 of unfossiliferous Silurian flags and slates, penetrated by masses of 

 Greenstone Porphyry ; at the base of the cliff, which is here called the 

 Bilberry rock, a mass of much-jointed and finely laminated dark grey 

 slates, highly inclined, and in some parts stained red and yellow, 

 were to be seen w^hen I visited the place some months since ; as, 

 however, it, with the flaggy beds immediately adjoining, was being 

 quarried away, this fine Graptolite-locality may soon disappear, or 

 has perhaps already disappeared. These slates are crowded with 

 well-defined, although much compressed Graptolites ; and as the 

 layers separate with great facility, good specimens were readily ob- 

 tained. The species are few, but abundantly repeated, Diplograpsus 

 pristis being the most numerous : it occurs MT.th prolonged axis and 

 proximal termination. The next species in point of numbers is a 

 diverging form, the initial process being well shown in some examples 

 which I believe to be identical with the species Dr. Mcholson figures f, 

 and refers to Didymograpsus {Graptolithus^ Jlaccidus, Hall. Mr. Car- 

 ruthers has described this species under the name of Didymograpsus 

 elegatis, doubting its identity with Hall's species ; I agree with him 



* The asterisks prefixed to species indicate their comparative abundance. 

 t Annals and Magazine of Natural History, ser. 4, vol. i. pi. 3. fig. 14. 



