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Eutainia sirtalis, (rion.)- 

 Garter Snake; Striped Snake. 



This is a snake which has a very wide distribution, and of which many 

 Tarieties are recognized. Many of these have been by various authors 

 regarded as distinct species. 



Eutainia sirtalis varies in form from slender to quite stout. The head 

 is distinctly marked off from the neck. The tail makes up from a fourth 

 to a fifth the entire length. The head is broad behind, narrowed in 

 front. Crown-shields 9, all well developed. Anteorbital 1. Postor- 

 bitals 3 or 4. Labials 7 or 8, the eye over third and fourth. Lower 

 labials 10. The scales are keeled, and arranged in 19 rows. The ven- 

 tral plates vary in number from 140 to 180. The subcaudals from 50 to 

 90 pairs. The anal plate is entire. 



The ground color varies from a light olive to black. This is usually 

 relieved by three greenish or yellow stripes, a dorsal and two lateral, 

 and by series of dark spots, some above, some below, the lateral stripes. 

 But of the stripes and spots some or all may be missing. The belly is 

 greenish or slate-color, usually with a series of black dots at the outer 

 ends of the ventral plates. 



Variety sirtalis. 



Coluber sirtalis, Linnseus, 1758, 64., ed. x, 222 ; Entainia shialis, 

 Baird and Girard, 1853, 6, 30; Tropidonotm sirtalis, Holbrook, 1842, 

 54, iv, 41, pi. 11 ; Garman, 1883, 13, 21, pi. 3, fig. 3. 



Dorsal stripe narrow, being encroached on by dorsal spots; lateral 

 stripes not conspicuous ; color above the faint lateral lines brown to 

 black, this containing three series of indistinct spots, each of about 70 

 from head to vent ; color immediately below lateral lines greenish ; ab- 

 domen with a row of black blotches on the ends of the ventral plates on 

 each side. All North America that is inhabitable by snakes. 



Variety dor salts. 



Eutainia dorsalis, Baird and Girard, 1853, 0, 30 ; Eutcenia sirtalis, 

 subsp. dorsalis. Cope, 1875, 12, 41. 



All three stripes broad and conspicuous; space above lateral bands 

 bright olivaceous, and containing a series of rather large spots, 74 in 

 number, from head to vent; abdomen greenish, witli a black dot on each 

 end of each ventral plate. Maine to Florida and Mexico. 



Variety ordinata. 



Coluber ordinatus, Jjmnssus, 1766, 64, ed. xii, i, 379; Eutainia ordi- 

 naia, Baird and Girard, 1853, 6, 32; Euta'uia siHalis subsp. ordinata, 

 Cope, 1875, 12, 41 ; Tropidonotm ordinatus, Holbrook, 1842, 04. iv, 45, 

 pi. 12. 



