566 Mr. J. Beete Jukes and the Rev. Samuel Haughton on the 



2. Carrickadaggan, county of Wexford. 

 Orthis Actoniffi, O. elegantula. Trinucleus seticornis, T. concentricus. 



Echinosphgerites aurantium. Lichas Hibernicus. 



Cybele arenosa, C. verrucosa. 



3. Newtown, county of Waterford. 

 Orthis simplex, 0. subrotundus, O. ele- Illcenus Bowmanni. 



gautula. Ampyx mammillatus. 



Ogygia Portlockii. 



i. Tramore, county of Waterford. 

 Orthis parva. Cybele verrucosa. 



Strophomena grandis. Phacops Brongniarti. 



Calymene Bluraenbachii? (? duplica- Encrinurus intermedins. 



tus). Remopleurides dorsospinifer. 



Acidaspis Jamesii (or bispinosus). 



Beneath the beds which contain those fossils is a great thickness of other 

 similar beds devoid of fossils. It is possible, perhaps probable, that these lower 

 beds are of the age of the Llandeilo flags of Wales. 



Whether there be any part of the series corresponding in age to the still 

 lower group of the Lingula flags is yet more doubtful. 



If the Lingula flags be altogether absent from their proper place between 

 the Cambrian formation and the Bala part of the Cambro-Silurian series, their 

 absence may be accounted for in the following manner: — 



In North Wales, where the Lingula flags are present, there is apparently 

 a perfect conformability from the Cambrian rocks up to the Bala beds: in 

 Wicklow, on the other hand, there is a complete unconformability between 

 the Cambrian formation and the black slates of the Cambro-Silurian series. 

 In the hills a little west of Ashford, the dark gray or black slates of the 

 Cambro-Silurian series may be seen stretching across the upturned and de- 

 nuded edges of a series of purple slates belonging to the Cambrian, and probably 

 to the lower part of the Cambrian series. 



Tlie interval thus proved to have been occupied by a destructive action 

 over tlie area which is now part of the county of Wicklow may have coincided, 

 in whole or in part, with the interval occupied by forces of production in the 



