314: Proceedings of the Royal Irish Academy. 



plimging ice of the maxiniiun phase. There was \'irfenally no late-glaeial 

 eorrie period. 



J 11 conclusion, I wish to express my thanks to the Geological Society of 

 London for the Daniel-Pidgeon award, made in the year 1916 to farther this 

 research; to my brother, Geoi^ge K. Charlesworth, for assistance in many 

 ways ; to Mr. "W. B. Wright and Dr. A. B. Dwerryhouse, for helpful 

 clitieism and suggestions:, and, above aU, to Professor P. F. Kendall, for 

 his inspiring lectures on Glacial Gteology, both in the lecture-room and in 

 the field, and for the great interest he has invariably evinced in the progi ess 

 of this research. 



DESCEU'TIOX OF PLATES VIII AKD IX. 



Plate VIIL 



Map, showing the chief glacier-lakes and overflow channels in existence 

 at four of the more important stages during the retreat of the ice-sheet off 

 the Sperrin Mountains. 



Scale : 5 miles = 1 inch (1 : 316,800). 



Plate IX 



Map, illustrating the salient features of the Glaciation of X.-W. Ireland ; 

 the western limit of the Scottish Ice; the lines of ice-flow over the whole 

 region from the Bamesmore centre of radiation and the Don^al lee shed ; 

 the distribution of the Bamesmore granite boulders ; the distribution of the 

 shelly drift (Sr ; the location of the superimposed boulder clays, eastern and 

 western (asteriskj ; the positions of the moraines and overflow channels ; 

 the re-advance of the Scottish Ice. 



Scale: 5 miles = 1 inch (1 : 316,800). 



