shown on Fig. 2], San Juan
County, New Mexico, some 18 miles southeast of the Park, 75987-76000.
The data shown in Figure 3 indicate that females are pregnant at least
from in August into November. A smaller percentage of females was
pregnant in November than in August or September. The fact that all
females more than 130 mm. long were pregnant in September suggests an
autumnal peak in breeding activity. A change in the ratio of small
individuals (less than 130 mm. in length) to large individuals (130 mm.
or more in length) is indicative of a sustained breeding period
throughout the time shown. In August the ratio was 1 to 2.3, in
September the ratio was 1 to 1.2, and the ratio was 1 to 0.7 in
November. The western harvest mouse is found usually in grassy areas.

Peromyscus boylii rowleyi (J.A. Allen) Brush Mouse

_Specimens examined._--Total, 14: North end Mesa Verde National
Park, 7000 ft., 76002-76003; Far View House, 7700 ft., MV 7851/507,
7854/507; Far View Point, 5 uncatalogued specimens in preservative;
1/2 mi. N Spruce Tree Lodge, 34742; 25 mi. [by road] SW Mancos,
149094 and 149096 USNM; Oak Tree Ruin, 6700 ft., MV 7870/507; and
Cliff Palace, 6800 ft., MV 7864/507.

The specimens were taken in August, September, and November. One adult
female trapped on September 10, 1958, had six embryos.

Peromyscus crinitus auripectus (J.A. Allen) Canyon Mouse

_Specimens examined._--Total, 3: Mesa Verde [Spruce Tree Cliff
Ruins], 149095 USNM; Balcony House, MV 7865/507, 7866/507.

Peromyscus maniculatus rufinus (Merriam) Deer Mouse

_Specimens examined._--Total, 396: North end Mesa Verde National
Park, 7000 ft., 76004-76100; Prater Canyon, 7600 ft., 76101-76144,
MV 7839/507, 7840/507; Upper Well, Prater Canyon, 7575 ft.,
69328-69329; Morfield Canyon, 7600 ft., 76145-76184; Park Point,
8525 ft., 69330-69342, 69344-69360; 1-1/2 mi. E Waters Cabin, 6400
ft. (labels on some specimens read "West Bank Mancos River,
Northeast side Mesa Verde National Park"), 69361-69376,
76185-76204; Sect. 27, head of east fork Navajo Canyon, 7900 ft.,
69377-69380, 69422-69426; 3 mi. N Rock Springs, 8200 ft.,
69403-69410; 2 mi. NNW Rock Springs, 7900 ft., 69411-69412; 1 mi.
NNW Rock Springs, 7600 ft., 69413-69418; 1/2 mi. NNW Rock Springs,
7500 ft., 69419-69421; Far View Ruins, 7700 ft., 69386-69402; Far
View Point, 76530-76531, 79