1040 



REPORT OF NATIONAL MUSEUM, 1898. 



of every other row of scales along the median and lateral stripes. On 

 stretching the skin, these marks are seen to be parts of narrow brown 

 crossbars, a superior row alternating with an inferior row, each occu- 

 pying about a scale in width. The number of these bars is generally 

 greater than in any other subspecies or species, ranging up to 103, but 

 sometimes they arc as few as 84, thus equaling some of the specimens 

 of ly\ couchii. The ground color is alike between all of them. There 

 is in adults a blackish cordiform mark on the nape, which represents 

 the nuchal spot in the E. e. couchii, etc., and the top of the head is like 

 the back, brownish clay color. 



In the specimen which has served as my type (Cat. No. 8731) the tail 

 enters the total length four and one third times. Gastrosteges, one 

 hundred and fifty-eight; urosteges, seventy-four; anal, one. 



In young specimens the dorsal spots are more distinct, but never so 

 large and distinct as in the J5J. e. lineolata. The top of the head is 



darker, and there are distinct 

 nuchal sj^ots, thus approach- 

 ing the E. e. couchii. There is 

 considerable difference in the 

 distinctness of the spots in 

 adults. Til us. Cat. No. 8727 

 (Taos, New Mexico), and Cat. 

 No. 5497 (Fort Bridger, Wyo- 

 ming) the spots are well marked 

 as in E. e. marciana, but those 

 below the lateral stripe are not 

 so distinct, being represented by 

 traces only. In Cat. No. Ol'O the 

 top of the head and nape are black, and the labials are bordered with 

 the same. The si)ecimen is small. On the other hand, in Cat. No. -"MI'S, 

 no sijots appear on the scales, and their existence is only discoverable 

 by stretching the skin. 



Measurements of sixteen specimens show the proportions of tlie tail 

 to the total length. Cat. No. 000, three and four-tifths times; Cat. No. 

 8730, four and one-third; Cat. No. 8735 ('J), four and one fifth and three 

 and four-fifths; Cat. No. 11725, three and four-fifths; Cat. No. 0514 (3), 

 four and four and two fifths; Cat. No. 5351 (2), four and four and one- 

 fourth; Cat. No. 926, four and one-tenth; Cat. No. 8720, four and two- 

 fifths; Cat. No. 8723, four and one fifth; Cat. No. 5226, four; Cat. No. 

 7237, three and two-thirds; Cat. No. 8728, three and two-thirds, 



This form inhabits the central regions of North America, including 

 the three topographical divisions — the Great Plains, the Colorado Basin, 

 and the Nevada Basin. It is not known from the Sonoran region, and 

 occurs doubtfully in the Western, but reaches it at Walla Walla, Wash- 

 ington. A specimen (Cat. No. 901) of this form is said to come from 

 Humboldt Bay, ( 'alifornia, but this locality may be held under advise- 



I 



ri<;.287. 



EUT^NIA BLEliANS VAGEANS BAIRD AND GlRAHI) 



= 1. 



Camp 12, Nevada. 



Cat. No. 11725, U.S.N. M. 



