REVISION OF THE KING SNAKES. 



77 



then reliance should be placed on the totality of characters. Adult 

 specimens which show no basal shading of the scales of the white 

 rings can be only hoylii. If basal shading is present, hoylii may be 

 distinguished from conjuncta by the fact that the infralabials are 

 usually 9 instead of 10, the frontal plate has usually a right or obtuse 

 posterior angle instead of an acute one, and its outline is distinctly 

 pentagonal instead of nearly trigonal. However, too much reliance 

 should not be placed upon these last two characters. If the number 

 of ventral plates is well above the average for yumensis and conjuncta, 

 the specimen is apt to be a hoylii. Adult examples of hoylii may 

 resemble yumensis, but if the head is much spotted posteriorly and 

 particularly if the wliite bars across the prefrontals are strongly 

 convex beliind and occupy more than half their area, it is a hoylii. 

 The accompanjdng table should prove useful in placing doubtful 

 examples, but since the distribution of these forms is fairly well known, 

 specimens may, with safety, be referred to their proper form by 

 locality only. 



Table of comparisons. 



Character. 



Yumenait. 



Boplii. 



Conjuncta. 





Usually 9 



Usually9 



Usually 10. 



Frontal 





Pentagonal 



More nearly trigonal. 



Posterior angle 



Postero-lateral angle . . 



Winterings: 



Adults 





Right or obtuse 



Usually distinctively 





Obtuse 



acute. 

 Nearly or quite 180 de- 







grees. 



Wliite scales always 



White scales only oc- 



White scales always dark 





dark brown at base. 



casionally dark brown 

 at base. 

 No basal shading of 

 white scales. 



brown at base. 



Young 



Usually like adults 



Xo basal shading of white 





scales. 



Head: Parietals, frontals, 



White spots very re- 

 stricted or absent. 



Usually like yumemif, 



Numerous wliite spots or 



supraoculars, second 



except in southern 



marks on these plates. 



and tliird rows of temp- 





California and north- 





orals: Adults and young. 





ern lower CaUfornia, 

 where it is usually like 

 conjuncta. 

 Usually rounded or an- 





Wliite bars on prefrontals: 



Usually simple bars oc- 



Like bof/lii. 



Adults and young. 



cupying less than half 



gular" posteriorly, and 







the area of the scute. 



occupying more than 

 half the area of the 









scute. 





Habitat and Tiahits. — ^Although this form has been known since 1853 

 there is very little recorded about its habits and habitat preferences. 

 Townsend (1887, 239) refers to it as "not uncommon on the Lower 

 McCloud, in damp places near the river." Hallowell (1859, 14) says 

 of it, "found in valleys and open prairies, very abundant, often 

 killed by travelers, and found lying on the roadside." A specimen 

 from Marin County, California, bears the note "by roadside in shade." 

 Merriam reports it (Stejneger, 1893, 204) as follows: "Found in the 

 valley of the Lower Muddy near an abandoned mill at Overton, 

 Nevada, where several were secured in dense thickets of Atriplex 

 torreyi. About dark they began to emerge from these retreats, 



