species is based
chiefly on specimens and living material from Kansas and northeastern
Colorado. A total of 520 live _parietalis_ has been examined from the
University of Kansas Natural History Reservation some 130 miles south
and a little east of the type locality in Nebraska. These probably
differ but little from typical specimens. The range of individual
variation in pattern is especially notable. In those from the
Reservation, the ground color varies from dull olive-brown to almost
jet black. The markings on the dorsolateral area vary in color, in
shade and in extent. These marks are chiefly confined to the skin
between the scales of rows three to nine. Although most typically
these marks are of some shade of red (hence the name "red-sided garter
snake"), they may be pale buff, or pale greenish yellow, or may even
have a bluish tint. In approximately ten per cent of the specimens
from the Reservation there is no red at all in the pattern, which
hence is similar to that of _T. s. sirtalis_ in the eastern United
States. Only a minority have all the dorsolateral marks red, and
in some of these specimens the marks higher on the sides are
progressively paler red, having a bleached out appearance. Most
typically the marks between rows three to six are some shade of red
while the smaller marks between rows six to nine are pale--yellowish,
greenish, or buffy. In some the pale area of the lateral stripe is in
varying degrees suffused with red, which may extend onto the edges of
the ventrals and even to the underside of the tail.

_T. s. parietalis_ may be diagnosed, on the basis of these snakes from
northeastern Kansas, as follows: Size medium large (length 23.5 to
34.5, or, exceptionally 43.5 inches in adult males; 32.5 to 46.0
inches in adult females), dorsolateral color olive to black.
Approximately every other scale of the third row is bordered above and
anteriorly by a crescent-shaped area of scarlet colored skin. Similar
crescent-shaped areas border the scales of the fourth and fifth rows
and often two adjacent crescents meet at the ends of an intervening
scale and fuse forming an H-shaped mark. Placed alternately with these
markings are similar but smaller crescent-shaped markings on the skin
of the upper half of the dorsolateral area on each side bordering
every other scale of the sixth, seventh and eighth rows. The crescents
of this upper series also may fuse to form series of H-shaped markings
alternating with tho