VARIATIONS OP GAKTER-SNAKES. 



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proportionate number of western Washington specimens with two 

 is greater than in the series from 

 elsewhere in the range, while none 

 of the California specimens exhibit 

 more than one except those from 

 Fresno which have two. It should 

 be stated, however, that two out of 

 seventeen " intermediate" specimens 

 from "Oakland " also have two. Just 

 what this means is difficult to deter- 

 mine, but it is interesting to note 

 that the latitudinal variation in the 

 frequency with which the trait — two 

 preoculars — occurs in ordinoides is 

 exactly the same as in elegans. For 

 some time writers have been led by 

 the occurrence of this trait to adopt 

 one of two courses: (1) To separate 

 the forms with two preoculars and 

 class them with similar specimens of 

 elegans as a distinct form (?>isc?/toto) ; 

 (2) to credit the form with having 

 both a single or a double preocular. 

 The first view is untenable, since the ; 

 specimens with two preoculars are 

 identical with those with one, from ; 

 the same region, while, as I have 

 shown, the western specimens differ . 

 markedly in scutellation from the I 

 eastern examples. As I have in- ! 

 dicated under the discussion of , 

 elegans, reliance can not be placed \ 

 on this character as a diagnostic \ 

 one, and I believe that the evidence \ 

 of the other characters shows con- j 

 clusively that in ordinoides, as along ; 

 the western border of the range of ele- \ 

 gans and in the intermediate region 

 between the two forms, the occur- 

 rence of two preoculars is to be con- 

 sidered as an occasional variation. 

 The color is variable, and so nuich 

 so that it is difficult to determine 

 to what extent the differences are 

 geograpliic. Nevertheless I believe 

 that the material at hand indicates a generally paler color in the 



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