By identifying our specimens as _R. f. inexspectatus_ and _R. f. tenuis_, we are left without any specimens that we, ourselves, have examined, which are referable to the subspecies _R. f. toltecus_. The specimens from Los Reyes which Howell (1914:47) referred to _R. f. toltecus_ have not been seen by us, and we guess, on the criteria used by us, that the animals would be referable to _R. f. tenuis_. Because Dr. Emmet T. Hooper has a revisionary study of the Mexican _Reithrodontomys_ underway, we have not attempted to bring together all of the pertinent material from different collections as would be required for an ideally thorough analysis of the geographic variation in _Reithrodontomys megalotis_ and _Reithrodontomys fulvescens_. As illustrative of statements made concerning the average size of _Reithrodontomys fulvescens_, the following measurements, all of specimens with much wear on each of the molar teeth, are recorded. Table headings: A: Number averaged or catalogue No. B: Sex C: Total length D: Length of tail E: Length of hind foot F: Basilar length G: Length of nasals H: Zygomatic breadth I: Mastoid breadth J: Alveolar length of maxillary tooth-row ========================================================================= LOCALITY A B C D E F G H I J ------------------------------------------------------------------------- Vall. Mex. 3 [M][M] 200 114 22.0 17.6 9.3 12.0 10.7 3.7 Pátzcuaro 5 [M][M] 170 101 20.6 16.7 8.7 11.6 10.6 3.7 Zamora 100215 [M] 153 82 19.0 15.9 7.8 10.9 10.3 3.5 Zamora 100275 [M] 184 101 21.0 16.5 8.0 11.1 10.4 3.6 Tacámbaro 5 [M][M] 159 91 19.4 15.5 8.0 10.5 9.6 3.3 Vall. Mex. 3 [F][F] 184 103 21.0 16.6 8.7 11.4 10.6 3.6 Pátzcuaro 5 [F][F] 182 104 21.6 16.8 8.6 11.6 10.5 3.6 Zamora 5 [F][F] 159 91 19.0 16.0 8.4 11.4 10.0 3.5 Tacámbaro 5 [F][F] 149 87 18.6 14.9 7.7 10.4 9.5 3.4 ------------------------------------------------------------------------- Note: [M] = Male and [F] = Female. =Reithrodontomys fulvescens inexspectatus= Elliot Fulvous Harvest Mouse; Spanish, Ratón Moreno _Rhithrodontomys inexspectatus_ Elliot, Field Columb. Mus. zoöl. ser., 3:145, February, 1903, type from Pátzcuaro, Michoacán. _Reithrodontomys fulvescens toltecus_, Howell, N. Amer. Fauna, 36:51, June 5, 1914, part. _Range_.--Central Michoacán; limits of range unknown. _Specimens examined_, 15: nos. 100278-100292, distributed by localities as follows: 3 mi. N Pátzcuaro, 6,800 ft., 6; 3 mi. NW Pátzcuaro, 6,700 ft., 3; 2 mi. W Pátzcuaro, 7,600 ft., 2; 2 mi. W Pátzcuaro, 7,700 ft., 4.