Part 18

Range.--Semitropical and tropical western part of the state.

Specimens examined, 14: nos. 52018-52023, 52063-52070, from 1,040 ft., 10 kms., W Apatzingan.

Remarks.--These specimens are notably paler and have shorter tooth-rows than those referred to O. c. regillus.

=Oryzomys fulvescens lenis= Goldman

Fulvous Rice Rat; Spanish, Rata Arrocera Pigmea

Oryzomys fulvescens lenis Goldman, Proc. Biol. Soc. Washington, 28:130, June 29, 1915, type from Los Reyes, MichoacAin; N. Amer. Fauna, 43:91, September 23, 1918.

Range.--Semitropical parts of state.

Remarks.--The type and one topotype so far as we know are the only specimens of this species to have been obtained from the state. The size is hardly larger than that of a large Reithrodontomys.

=Sigmodon melanotis= Bailey

Fulvous Cotton Rat; Spanish, Rata Algodonera Leonada

Sigmodon melanotis Bailey, Proc. Biol. Soc. Washington, 15:114, June 2, 1902, type from PAitzcuaro, 7,000 ft., MichoacAin.

Range.--Central MichoacAin, as now known.

Specimens examined, 8: nos. 100623-100626, 52089-52092, distributed by localities as follows: 2 mi. W PAitzcuaro (7,400 and 7,700 ft.), 2; 3-1/2 mi. S PAitzcuaro, 7,800 ft., 2; TancA-taro, 6,000 ft., 4.

Remarks.--This species was taken along with the species S. hispidus two miles west of PAitzcuaro, and can be easily distinguished from the latter by the dark reddish as opposed to grayish color of the upperparts and by the shorter hind foot (less instead of more than 32.5 mm.).

=Sigmodon hispidus mascotensis= Allen

Hispid Cotton Rat; Spanish, Rata Algodonera Setosa

Sigmodon mascotensis Allen, Bull. Amer. Mus. Nat. Hist., 9:54, March 15, 1897, type from San SebastiAin, near Mascota, Jalisco.

Sigmodon hispidus mascotensis, Bailey, Proc. Biol. Soc. Washington, 15:108, June 2, 1902.

Range.--Larger part of state.

Specimens examined, 4: nos. 100629, 3 mi. N PAitzcuaro, 6,700 ft.; 100630, 2 mi. W PAitzcuaro, 7,700 ft.; 100632, 1-3/4 mi. S TacAimbaro, 5,700 ft.; 100631, 6 mi. S and 1 mi. E TacAimbaro, 4,000 ft.

Remarks.--Bailey (1902:109) records a "very large" specimen from QuerA(C)ndaro. Our specimens have shorter molariform tooth-rows than do those from nearer the type locality, for example, those from Tuxpan, Las Canoas, and Artenkiki, all three places in Jalisco.

=Sigmodon hispidus atratus= Hall

Hispid Cotton Rat; Spanish, Rata Algodonera Setosa

Sigmodon hispidus atratus Hall, Proc. Biol. Soc. Washington, 62:149, August 23, 1949, type from 6-1/2 mi. W Zamora, 5,950 ft., MichoacAin.

Range.--Known only from Zamora and the type locality.

Specimens examined, 2: nos. 100628 (the holotype), 6-1/2 mi. W Zamora, 5,950 ft.; 120268 (U. S. Nat. Mus., Biol. Surveys Coll.), Zamora.

Remarks.--When the present account first was prepared our specimen from six and a half miles west of Zamora was tentatively referred to S. h. mascotensis. Subsequently a second specimen, from Zamora, was found. It agreed with the specimen from six and a half miles west of Zamora. Inasmuch as the second specimen agrees with the first and since each of the two differs from any previously described kind, a name and description were published in time to be inserted in the present account. From S. h. mascotensis, S. h. atratus differs in shorter hind foot, darker upper parts, more densely haired tail, shorter skull, more convex dorsal longitudinal outline of skull, posteriorly constricted anterior palatine foramina instead of parallel-sided foramina, and shorter and less decurved anterior process of maxillary arm of zygoma.

=Neotomodon alstoni alstoni= Merriam