652 North American snakes — cope. 



I 



This species resembles in some of its forms tlie E. sirtaUs, but it is 

 to be always distiugaislied by the tweuty-one rows of scales, the eight 

 superior labials, aud from most of the forms of the latter, by the absence 

 of a series of rounded spots near the end of the gastrosteges. In its 

 range it never enters the eastern nor austroriparian regions, except- 

 ing the latter at the extreme western part of Texas, on the Concho 

 and Nueces rivers and their tributaries. 



The labial and scale formuke in this species are quite constant. In 

 two specimens of the E. e. plutonia the labials are eight, and the 

 scales in twenty-one rows. In two of E. e. elegans, the figures are the 

 same. In two of ^. e. brunnea, the figures are the same. In eight of 

 the E. e. lineolata, the figures are the same. In four of the E. e. couchii 

 the figures are the same, except in one individual, where there are but 

 nineteen rows of scales. In twenty-two specimens of E. e. vagrans 

 there are twenty-one rows of scales in all, and in five specimens there 

 are seven superior labials on one side. In one only are there 

 seven superior labials on both sides. In all the others there are 

 eight labials on both sides. In twelve specimens of E. e. marciana, 

 all have eight upper labials, and all but two twenty-one rows of scales. 

 In two the scales are in nineteen rows. Thus in fifty-one specimens 

 there are three departures from the regular scale formula; and one en- 

 tire departure and five partial departures from the labial formula. 



There are eight well marked color forms of this species, which mostly 

 occupy distinct geographical regions, and are abundantly entitled to 

 be called subspecies. It is indeed possible that some of these might be 

 as well regarded as species, but the existence of transitions, and the 

 lack of importance in the characters themselves, induce me to consider 

 them as subspecies. They are, however, in the great majority of cases 

 easily recognized. The characters of these forms are as follows : 



I. No spots ; labials not dark bordered. 



Black above and below; uo lateral band; dorsal band wanting or a trace in front 

 only E. e. jylutonia. 



Black above, light below; three distinct stripes, all black bordered ...E.e. elegans. 



Brown above, light below; three stripes, not distinctly bordered... Z?. e.hrunnea. 

 II. Spotted ; labials not dark bordered; unchal spots Indistinct. 



Stripes aud spots distinct ; the superior row of spots condiient into a band ; the 

 inferior separated by chestnut-red spaces; belly olivaceous..^, e. ordinoides. 



Spots large anteriorly, smaller or confluent posteriorly; interspaces indicated by 

 pale edges of the scales ; bands distinct E. e. Hneolata. 



Spots small, numerous, 80-100, interspaces large, pale; bands present often in- 

 distinct ; belly with dark middle E. e. vagrans. 



III. Spotted; labials dark bordered ; nuchal spots more or less distinct. 



No dorsal band, lateral band indistinct; intermediate space lead-colored witli 

 one row of spots next to the lateral band; yellow marks behind eye iucom- 

 p letc E. e. couch ii. 



Dorsal and lateral bands indistinct ; three rows of spots on a light ground on 

 each side ; two yellow crescents extending upwards,^! angle of mouth and 

 behind eye E. c. viureiana. 



