Lo 
ew 
I 
CHAPTER XIX. 
COUNTY AND DISTRICT DISTRIBUTION, 
METHOD OF INVESTIGATION—SOURCES OF INFORMATLON— 
COMPARISON OF RESULTS OBTAINED. 
Tue study of the variations of the species in any 
given order of animals is one of the most fascinating 
in Natural History, and what follows in this book is 
an attempt to indicate the most important differences 
of distribution and relative frequency of our three 
British serpents; and as it is, as far as I am aware, 
the first attempt of its kind in this branch of our 
fauna, it must necessarily be imperfect. A perusal 
of the various county records will show that it would 
be the work of a lifetime for any one investigator to 
thoroughly work up the Ophidia of every county, 
even in a small country such as ours. The only 
practicable method is to enlist the aid of field natural- 
ists all over the land, and compare and tabulate the 
results so obtained. This has been the method 1 
have adopted, being encouraged to do so by the very 
