2 BULLETIN 114, UNITED STATES NATIONAL MUSEU!^I. 



Every means has been taken to make the present review as accurate 

 and as complete as possible. Specimens have been borrowed from 

 many collections, both public and private, throughout the United 

 States. The assembling thus of a great many specimens not pre- 

 viously reported upon has helped greatly to a better understanding 

 of the distribution and relationships of the various forms. Every 

 specimen has been subjected to a careful examination of structm-al 

 and color pattern features. The former have of course been regarded 

 as of more significance than the latter in establishing relationships, 

 but, as a matter of fact, when the patterns of two specimens were 

 similar and the structural features different it was evident in nearly 

 every case that the resemblance in patterns was only superficial or 

 general, and that features easily overlooked were usually present to 

 confirm the fundamental differences. 



It is fully realized that the present effort is but a preliminary at- 

 tempt at an understanding of the genus, and for this reason care has 

 been taken not to obscure features that may later prove to be of 

 importance. Nothing is to be gained by ' 'lumping" of doubtful 

 forms; apparent constancy throughout a definite geographic range 

 has been deemed sufficient to warrant recognition by name, and inter- 

 gradation has been the criterion of subspecific distinction. If an 

 error has been made, the name will call attention to it, and will 

 result in ultimately determining the proper status of the form. 

 However, it is believed that more abundant material will increase 

 rather than diminish the number of forms now recognized, and, 

 where the material has suggested such a possibility, attention has 

 been drawn to the fact. 



About 1,600 specimens have been assembled for examination. 

 This is but few, to be sure, when compared with the numbers often 

 available in other groups of animals, but very good for king snakes, 

 for it should be noted that the great bulk of this number is the result 

 of chance collecting of forms that are, in general, not plentiful any- 

 where, and that it is more than four times as many as could ever 

 have been examined by any previous reviewer. Nearly all the type 

 specimens of the genus are in the United States National Museum, 

 in Washington, and the Academy of Natural Sciences of Philadelphia, 

 and these have been examined. One hindrance to the work has been 

 the occasional lack or ambiguity of information as to locality. Speci- 

 mens without locality labels or with vague or indefinite localities are 

 valueless, and those with incorrect labels are worse than useless, be- 

 cause they are apt to be misleading. Collectors can not be too care- 

 ful about attaching to their specimens exact information as to locality 

 as soon as possible after collecting, and if they wiU also attach brief 

 notes on habitat, they will add much to the value of the specimens. 



It is hoped that the present work will emphasize the serious 

 inadequacy of our knowledge of the king snakes. The maps of distri- 



