48 Mr. Joseph Wright on 



With the exception of sixteen samples received from Novaia 

 Zemlia which, on account of the smallness of their size, had to 

 be examined in detail under the microscope, floatings from the 

 clays were alone examined. To ascertain how far the process 

 of floating could be relied on for giving conclusive results, one 

 ounce troy of the boulder clay from Woodburn, Carrickfergus, 

 was examined with great care. The first floating contained 

 1,400 specimens, this process having to be repeated twenty-four 

 times before specimens ceased to come up. What remained 

 of the clay was then examined under the microscope, and 

 sixty-seven additional specimens were got from it. Upwards of 

 2,100 specimens were obtained from this ounce of clay. This ex- 

 perimentclearlydemonstrated that the process of floating cannot 

 be relied on for proving the non-existence of Foraminifera in 

 Boulder Clay. 



The micro-fauna of the Boulder clay is a peculiar one, 

 more than half of the entire specimens found being referable to 

 Nonionina depressula, whilst Cassidnlina crassa, though some- 

 what rare as a recent British species, is often plentiful. The 

 Porcellanous forms are usually very rare, whilst the Arenacea 

 are represented only by the species Haplophra^mimn 

 canariense. 



The marine fauna in a climate so rigorous as must have pre- 

 vailed during the glacial period could not fail but be a poor 

 one. Mr. S. A. Stewart, in his " Mollusca of the Boulder Clay 

 of the North East of Ireland,"says : — " Molluscan shells occuring 

 in the Boulder clay are not numerous. In most cases they are 

 only got by patient searching, and then only in a fragmentary 

 condition ; but in a few instances they are less rare, and include 

 specimens in a perfect state. The presence of perfect shells of 

 Leda was known long since to General Portlock, and forced 

 him to the same conclusion as arrived at by the author, that 

 the Boulder clay is a marine sedimentary deposit."* 



No doubt many of the shells in boulder clay were transported 



*Proc. Belfast Nat. Field Club. App. 1879-80. 



