Vol. VIII] VAN DENBURGH AND SLEVIN— GARTER-SNAKES 



265 



Synonyms. — Cliilopoma rufopiinctatum Cope, 1875; type 

 locality "Southern Arizona." Atomarchus multimaculatus 

 Cope, 1883; type locality San Francisco River. 



Range. — This species occurs in the northern part of the 

 Mexican plateau south to Coahuila and Durango and north to 

 portions of southwestern New Mexico and southern and cen- 

 tral Arizona. The original Arizonan specimen was labeled 

 merely "Southern Arizona," and no definite locality in that 

 state was recorded until our specimens were secured at 



1. Oak Creek, Coconino County, Arizona. 



Material. — We have eighteen snakes of this species from 

 the above locality. 



Variation. — The loreals are 1 — 1 in seventeen and 1 — 2 in 

 one. The preoculars are 2 — 2 in sixteen, or 89% ; 2 — 3 in 

 two, or 11%. The postoculars are 3 — 3 in ten, or 56%; and 

 3 — 4 in eight, or 44%. The temporals are 1 + 1 — 1 + 1 in nine, 

 or 50% ; 1 + 1—1+2 in eight, or 44% ; and 1+2—2+2 in one, 

 or 6%. The supralabials are 8 — 8 in thirteen, or 72% ; 7 — 8 in 

 two, or 11% ; 8 — 9 in two, or 11% ; and 7 — 7 in one, or 6%, 

 The infralabials are 10 — 10 in nine, or 53% ; 9 — 10 in four, or 

 24% ; and 9 — 9 in four, or 24%. The scale-rows are 21 — 19 — 

 17 in all. The gastrosteges vary in number from 161 to 177, 

 males having from 165 to 177, females from 161 to 170; the 

 average in eleven males is 171.3, in seven females, 164.9. The 

 urosteges vary from 69 to 87, males having from 80 to 87, 

 females from 69 to 82 ; the average in eleven males is 84.2, in 

 seven females, 73.9. These variations are shown in full in the 

 following table of scale-counts. 



