INTRODUCTION. XV 



desire to express my best thanks. It was upon these single 

 returns that I depended in great measure for assistance in 

 tracing out the steps of advance ; and from the letters of my 

 many obliging correspondents I often culled interesting 

 additional facts. 



I may mention that I have distributed more than 450 

 circulars to parties situated in all parts of the area at present 

 occupied or visited by the species. By far the larger portion 

 of these have been returned with the answers filled in, more 

 or less fully, according to the amount of information my vari- 

 ous correspondents had to impart. 



Finally, Eobert Warren, Esq. of Moyview, Sligo, Colonel 

 Edward H. Cooper, of Markree Castle, Sligo, and A. G-. More, 

 Esq., Dublin, have rendered me valuable assistance, some of 

 the results of which will be found in the Appendix, as they 

 arrived somewhat too late for insertion in the text : and to 

 my friend Mr. Eobert Currie I am indebted for the careful 

 and beautiful execution of his subjects, in illustrating the 

 text, with the frontispiece, vignette, and other pieces. 



