k-bunch grass associations, it seems to reach its greatest abundance
in marshes on the Mexican Plateau at elevations of 1550 to 2300 meters.

~Thamnophis melanogaster canescens~ Smith

_Thamnophis melanogaster canescens_ Smith, Zoologica,
27:117, October 23, 1942.--Chapala, Jalisco, Mexico.

Lago de Cuitzeo (5); Lago de Patzcuaro; Patzcuaro;
Tacicuaro; Tangamandapio (2).

This species of garter snake seems to be most abundant in the marshes
adjacent to the lakes on the Mexican Plateau in Michoacan and Jalisco.
At these elevations (1550 to 2200 meters) it often is found in
association with _Thamnophis eques eques_ and sometimes with _Thamnophis
dorsalis cyclides_. On June 11, 1958, individuals of this species were
found in a hyacinth-choked marsh at Tangamandapio at night.

One specimen from Tangamandapio (UMMZ 119414) had, in life, a dark
chocolate brown dorsum, reddish brown sides, and cream-colored belly,
chin, and labials. There were no longitudinal dorsal stripes.

~Thamnophis scalaris scaliger~ (Jan)

_Tropidonotus scaliger_ Jan, Elenco sistematico degli Ofidi,
p. 70, 1863.--No type locality designated. Type locality
restricted to Mexico City, Distrito Federal, by Smith and
Taylor (1950a:329).

_Thamnophis scalaris scaliger_, Smith, Zoologica, 27:103,
October 23, 1942.

Cerro Tancitaro (2); Nahuatzen; Opopeo; 26 km. S of
Patzcuaro.

The few specimens of this species from Michoacan have been collected at
elevations from 1800 to 3400 meters in pine or fir forest in the
Cordillera Volcanica.

~Micrurus distans michoacanensis~ (Duges)

_Elaps diastema michoacanensis_ Duges, La Naturaleza, ser.
2, 1:487, 1891.--Michoacan. Type locality restricted to
Apatzingan, Michoacan, Mexico, by Smith and Taylor
(1950a:335).

_Micrurus distans michoacanensis_, Zweifel, Amer. Mus.
Novitates, 1953:11, June 26, 1959.

Apatzingan (6).

All specimens were collected in the arid scrub forest of the
Tepalcatepec Valley. The number of black rings on the body varies from
six to eleven. In this respect they agree with the diagnosis of this
subspecies presented by Zweifel (1959b:9).

~Micrurus laticollaris~ (Peters)

_Elaps marcgravii laticollaris_ Peters, Monats. Akad. Wiss.
Berlin, p. 877, 1869.--Izucar de Matamoros, Puebla, Mexico.

_Micrurus laticollaris_, Schmidt, Publ. Field Mus. Nat.
Hist., z