Vol. \"in] WAX DEXBURGH A\'D SLEVIN— GARTER-SNAKES 



205 



Material. — Twenty-one specimens from these four localities. 



Variation. — The loreals are 1 — 1 in all. The preoculars are 

 1 — 1 in all but one which has 1 — 2. The postoculars are 3 — 3 

 in all but three which have 3 — 4. The temporals are 1+2 — 

 1+2 in fourteen, 1+2 — 1+3 in three, 1+3 — 1+3 in three, 

 and 2+3 — 2+3 in one. The supralabials are 8 — 8 in twenty, 

 and 8 — 9 in one. The infralabials are 10 — 10 in seventeen, 

 11 — 11 in two, 10 — 11 in one, and 9 — 10 in one. The scale- 

 rows are 19 — 19 — 17 in all but one which has 21 — 19 — 17. 

 The gastrosteges vary in number from 164 to 175, males having 

 from 166 to 175, females from 164 to 171 ; the average in thir- 

 teen males is 170.6, in seven females, 168. The urosteges vary 

 from 77 to 97, males having from 85 to 97, females from 77 to 

 88; the average in twelve males is 91.7, in six females, 83.5. 



The series is too small to show the real limits of variation. 

 The scale-counts are given in full in the following table. 



Remarks. — Specimens from Mexico and Central America 

 seem to differ from those from Arizona and New Mexico in 

 the frequent reduction in the number of supralabials to seven. 

 Since our material is all from Arizona we are unable to form an 

 opinion as to whether the snakes from these distant localities 

 are really identical in other respects. 



