_Remarks._--The 22 specimens in the Chicago Natural History Museum are remarkably uniform in color in spite of differences in age; 17 are so young as to have the first upper molar only slightly worn and 5 are adults. In preparing the original description of _R. c. seclusus_, known only from specimens in the summer pelage, comparison of color was made with only the winter pelage of _R. c. chrysopsis_ and it was pointed out that the differences noted in color between the two subspecies might be seasonal rather than subspecific. A summer specimen of _R. c. chrysopsis_ (K. U. 17980, taken on June 15, 12 km. ESE Amecameca, 11,500 ft.), is available as the present account is being written. In direct comparison with the original material of _R. c. seclusus_, all in summer pelage, and in comparison with a specimen of _R. c. chrysopsis_ in winter pelage (January 18), from 30 km. E Amecameca, the summer pelage of no. 17980 is more blackish than the winter pelage and therein more closely resembles that of _R. c. seclusus_. The same is true of the more sparsely haired tail. The ears, however, are blackish as in winter-taken _R. c. chrysopsis_. This feature and also the large size and different cranial proportions of specimen no. 17980 are in accordance with the differences between _R. c. chrysopsis_ and _R. c. seclusus_ as recorded in the original description of the latter. =Baiomys taylori analogus= (Osgood) Northern Pygmy Mouse; Spanish, Ratón Pigmeo Norteño _Peromyscus taylori analogus_ Osgood, N. Amer. Fauna, 28:256, April 17, 1909, type from Zamora, Michoacán. _Baiomys taylori analogus_, Miller, N. Amer. Land. Mamm., 1911, p. 137, December 31, 1912. _Range._--Northwestern part of state. _Specimens examined_, 35: nos. 100331-100365, distributed by localities as follows: 8 mi. N Zamora, 5,500 ft., 2; 11 mi. W Zamora, 5,750 ft., 1; 6-1/2 mi. W Zamora, 5,950 ft., 2; 4 mi. W Zamora, 5,450 ft., 1; 3 mi. NW Pátzcuaro, 6,700 ft., 21; 3 mi. N Pátzcuaro, 6,800 ft., 5; 2 mi. W Pátzcuaro, 6,700 ft., 3. _Remarks._--Osgood (1909:257) has recorded this subspecies also from Acámbaro and Los Reyes. We found that these animals got caught in our traps almost as often in the daytime as at night and concluded that they were less nocturnal, or at any rate more diurnal, than any of the other cricetine mice at the places in Michoacán where we trapped. =Baiomys musculus musculus= (Merriam) Tropical Pygmy Mouse; Spanish, Ratón Pigmeo Tropical _Sitomys musculus_ Merriam, Proc. Biol. Soc. Washington, 7:170, September 29, 1892, type from Colima, Colima. _Peromyscus musculus_, Allen and Chapman, Bull. Amer. Mus. Nat. Hist., 9:203, June 16, 1897. _Baiomys musculus_, Mearns, U. S. Nat. Mus. Bull., 56:381, April 13, 1907. _Range._--Dry, tropical, southwestern parts of state.