ON THE ROCKS OF ANGLESEY. 589 
Discussion. 
Dr. Hicxs, while, in the main, agreeing with the author so far as 
the Archean rocks go, was, as regards the Paleozoic beds, inclined 
to believe that Prof. Hughes was right. He thought the Trilobites 
referred to as of Ordovician age were referable to Niobe and Neseu- 
retus—Cambrian forms. He thought Orthis Carausii was confined 
to the Cambrian, and that it is associated in Anglesey with another 
Cambrian Orthis. The stratigraphical as well as the fossil evidence 
seemed to support Prof. Hughes’s view that the fossiliferous beds 
were of Tremadoc age. 
Dr. Rozerrrs thought that in Anglesey fies are contorted rocks 
of different ages, some probably not Archean. 
Mr. Harker also thought that the author had failed to distin- 
guish the fact that the altered rocks of Anglesey are not all of the 
same age. ‘he author’s supposed Pebidian beds were found, when 
traced to the northward, to be intercalated with conglomerates con- 
taining fossils. He agreed with Dr. Hicks in thinking that the fossils 
in the Paleozoic schists are Tremadoc and not Ordovician. 
Mr. Huptxston asked what evidence there was concerning the 
relations of the granitoid rocks and the Holyhead schists. 
The PrusipEnt said that the conglomerate contained fragments of 
the granitoid series, of schists similar to those of Holyhead, and of 
other rocks of comparatively unaltered character. He believed that 
all the true schists in Anglesey are of Archean age, though there 
were schistose beds of later date, which it was difficult in the field 
to distinguish from them. 
Dr. Catnaway said that, on the authority of Sir A. C. Ramsay 
and Mr. Etheridge, Meseuretws occurs in the Silurian. He accepted 
Dr. Woodward's identification of the Trilobites as of Ordovician age. 
He had before shown that the so-called “ gnarled schists” consist 
of two series, one little altered and the other truly metamorphosed, 
but both Archzan. He believed the rocks with Bala fossils in the 
north of Anglesey were let down into the midst of the Archean by 
faults. He had always held that the schists underlay the granitoid 
rocks. 
Q.J.G.8. No. 159. 2B 
