Oct. 1 9 19. The Irish Naturalist. 109 



FOSSIL SHELLS FROM WEXFORD AND MANXLAND. 



BY ALFRED BELL. 



When presenting the Reports on the Manure Gravels of Co. 

 Wexford to the British ^Association in 1887-1890, it appeared 

 to the writer that the theory of their glacial origin was not 

 well founded, nor borne out by their faunal contents, nor 

 by the way in which these were distributed; and this opinion 

 was confirmed later, when, visiting the country to the north 

 of the Peel-Ramsey line in the Isle of Man, he saw that the 

 same conditions prevailed there, not only in the strati- 

 graphical arrangement, but equally so in the fossils yielded 

 by the clays and sands exposed in this area. Subsequent 

 researches have intensified this conviction. According to 

 Mr. Hallissy,^ the basal bed of this series is a highly cal- 

 careous chocolate-coloured clay or marl (laid down by the 

 Irish Channel ice), which occurs over practically the whole 

 district, succeeded by shelly gravel and finely stratified sand, 

 the whole capped by a " stratum " of calcareous clay marl 

 of a drab colour (Griffiths). 



This order also prevails in the Isle of Man just referred to, 

 where, according to Prof. KendalF, the lower bed of dun- 

 coloured Boulder-clay contains a large quantity of small 

 stones, frequently well glaciated, and a great abundance 

 of shells in a fair state of preservation ; this agreeing with the 

 contents of the Wexford marls. The Manx clays vary in 

 texture from stony till to fine buttery clay. 



At one place Prof. Kendall met with a bed of fine tough 

 clay unlike any of the drift beds in the Irish Sea basin with 

 which he was acquainted, containing a well-preserved 

 boreal fauna, many of the bivalves having their valves still 

 in apposition. In this particular clay were one or two seams 

 of gravel which seemed to show signs of having been involved 

 in the clay by some kneading or shearing movement sub- 

 sequent to its formation. A very similar arrangement is 

 present in the Holderness clays on the Yorkshire coast. ^ 



^ Hallissy, T. : On the superficial deposits of the County of WeTcf rrd. 

 Irish Naturalist, VoL xxi., p. 175, 1912. 



^ Kendall, P. F., Yn Lioar Manninagh, vol. i., p. 398, 1894. 

 ^ Bell, A., Naturalist (Yorkshire), 191 8. 



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