The Micro-Fauna of the Boulder Clay, &V\ 49 



by icebergs with stones and rock fragments, but some of them 

 certainly lived at the places where they are now found, and 

 with some few exceptions, all the Foraminitera must have done 

 so, as these microzoa are usually as perfect and as fresh looking 

 as recent specimens brought up by the dredge. There were in 

 glacial times both elevation and subsidence. First glacial 

 striation, then depression, boulder clay, and marine organisms- 

 At Woodburn and Knock Glen, Leda pygmcea and L. 

 minuta are frequently found with their valves united, here also 

 Foraminifera occur in the very greatest profusion, 100 species 

 having been found at Woodburn and 79 at Knock Glen. 

 Foraminifera in boulder clay are usually much smaller in size 

 than recent British species, but many of the specimens at these 

 two localities are fairly large in size, the following are the most 

 notable in this respect : — M Molina semimMim, Nonionina 

 orbicularis and Polystomella arctica. Three of the species 

 found at Woodburn and five of those from Knock Glen are 

 only known as recent British species from gatherings taken off 

 the West Coast of Ireland, two of them also occurring off the 

 West Coast of Scotland. Some of these West of Ireland 

 species have also been found in boulder clay at other places. 

 Lagena fimbriata was got at five other localities, one of them 

 being Larch Hill, Co. Dublin, 650 feet above the sea, and 

 Polystomella subnodosa was got at Deppel Burn, Ayrshire, at 

 106 1 feet elevation. The presence of these West of Ireland 

 Foraminifera in the boulder clay of Woodburn, Knock Glen, 

 and some other places, would lead us to infer that when these 

 clays were deposited the land" stcod at a much lower level than 

 new, and when the marine conditions were somewhat similar to 

 what now prevails off the West Coast of Ireland. The fineness 

 of the clay at these two localities, and their freedom from atones, 

 the perfect condition of some of the Leda shells, the profusion 

 of Foraminifera, and the large size of some of the specimens, 

 would support the view that the clay at these two localities 

 was deposited in deep and quiet water, and below the disturb- 

 ing influence of ice action. Boulder clay with many stones in 



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