Pacific lowlands from Guerrero northward to Colima. Northward on
the Pacific lowlands from Colima to Sinaloa and in the
Balsas-Tepalcatepec Basin is found _I. gemmistratus latistratus_.

~Lampropeltis doliata~ (Linnaeus)

_Coluber doliatus_ Linnaeus, Systema naturae, ed. 12, 1:379,
1766.--Charleston, South Carolina.

_Lampropeltis doliata_, Klauber, Copeia, No. 1:11, April 15,
1948.

Coalcoman (3); El Sabino; 24 km. W of Morelia; Rio Nexpa;
Uruapan.

The few specimens of this species from Michoacan show a wide range of
variation; furthermore, the present systematic status of the subspecies
of _Lampropeltis doliata_ portrays an incongruous pattern of
distribution. Specimens from the Sierra de Coalcoman have relatively
narrow red bands that are not interrupted dorsally by extensions of the
black rings; the scales in the red bands have black tips. The specimen
from El Sabino (EHT-HMS 5253) and the one from the Rio Nexpa on the
coast (USNM 31491) have broader red bands; the scales in the red bands
do not have black tips. A specimen from 24 kilometers west of Morelia
(UIMNH 17782) and one from Uruapan (UMMZ 121508) have the red bands
interrupted dorsally by extensions from the black rings.

Specimens from the Sierra de Coalcoman were referred to _L. doliata
blanchardi_ by Peters (1954:24), who noted that in some characters
these snakes were like _L. d. nelsoni_ and in others like _L. d.
polyzona_. The individual from El Sabino was referred to _L. d. nelsoni_
by Taylor (1940c:465); the one from 24 kilometers west of Morelia was
referred to _L. d. arcifera_ by Smith (1942c:198). If these assignments
are correct, three subspecies of _Lampropeltis doliata_ occur in
Michoacan: _blanchardi_ in the Sierra de Coalcoman, _nelsoni_ on the
coast and in the Tepalcatepec Valley, and _arcifera_ on the Mexican
Plateau and in the Cordillera Volcanica. Such a distribution is
plausible, but the few specimens and our general lack of knowledge of
the variation and relationships of the different populations do not
permit a definite assignment at this time.

~Lampropeltis ruthveni~ Blanchard

_Lampropeltis ruthveni_ Blanchard, Occ. Pap. Mus. Zool.
Univ. Michigan, 81:8, April 28, 1920.--Patzcuaro, Michoacan,
Mexico.

Morelia; Patzcuaro; Tacicuaro.

At the present time this species is known definitely from only three
localities on the Mexican Plateau in Michoacan. An incomplete ski