IN THE UPPER GREEN SLATES OF NORTH WALES. 75 



succession being strangely alike. In Shropshire, North Wales, and 

 Ireland they have yielded a few indications of life, but these districts 

 need further exploration " *. How true was this last remark will be 

 seen in the sequel. 



On the 5th August last I received a letter and box of specimens 

 from Professor James J. Dobbie, of the University College of North 

 Wales, Bangor, accompanied by the following statement : — 



" The specimens of Trilobite, Nos. 1 & 2, were found by Robert 

 Edward Jones and Robert Lloyd, two quarrymen employed in the 

 Penrhyn Quarry, Bethesda, near Bangor. 



" As no fossils had ever been found in this quarry before, the dis- 

 covery excited considerable interest in the locality, and the quarry- 

 men brought the specimens to the University College, and left them 

 in my hands for examination. Some doubt having been thrown, by 

 residents, upon the authenticity of the specimens, I visited the 

 quarry along with the men on the 18th June, and examined them 

 minutely as to the circumstances of the discovery. 



" The place where they allege they found the fossil is in an old 

 working of what is known as the ' Upper Green Bed ' of the 

 quarry. This bed, which is about 150 feet in thickness, is the 

 highest in the quarry. It immediately underlies the Grits forming 

 the brow of Bronllwyd, and is itself underlain by a bed of purple 

 slate. The fossils were found close to the junction of the ' Green 

 and Purple Slates.' 



" The men showed me the block from which the fossil was taken, 

 and I could detect no difference between the slate of which the block 

 is composed, and the slate in which the fossil lies imbedded." 



" Whilst searching amongst the debris close by," writes Prof. 

 Dobbie, " I found specimen No. 3 " (which has since been deter- 

 mined to be the obliquely squeezed head of a second example of the 

 same Trilobite, see PL IV. fig. 2). 



Prof. Dobbie adds : — '^ The men who found the specimen are very 

 intelligent quarrymen, and have made some little study of geology. 

 They were in the unused working for the purpose of examining its 

 geology, when they discovered the Trilobite." 



I think, if any doubt at all existed about the genuineness of the 

 " find," that is now entirely removed by the fact that Prof. Dobbie 

 was so fortunate as to knock out a second specimen with his own 

 hammer. 



The specimens have been seen and examined by Dr. Hinde and 

 Mr. A. S. Foord, both of whom know the American Lower Palaeo- 

 zoics very well, and they do not recognize these specimens as at all 

 resembling, lithologically, any North- American rock f. 



Dr. Hinde has also pointed out that the freshness and sharpness 

 of the specimens is opposed to their having been carried about by 

 workmen, in which case the angles would have become abraded, and 

 the surface of the matrix greasy from handling. Prof. Bonney was 



* See Proc. Geol. Assoc. 1872, vol. iii. pp. 101-103. 



t It had been suggested that one of the men, who had worked in slate- 

 quarries in America, might have brought the specimens over with him. 



