No. 572] NOTES ON MEADOW JUMPING MOUSE 489 



perature for this section being only 3° F. (February 10, 

 1913,) the mouse did not survive the cold weather, and 

 was found dead, when the cage was opened on June 17, 

 1913. 



The nest was found to be located in the extreme end of 

 the sod, only 1^ inches from the top and about 1 inch from 

 the edge. It was roughly oval in shape, being hollowed 

 out of the loam and lined with a few blades of grass. It 

 measured roughly If inches by 1^ inches and was just 

 large enough to contain the mouse when curled up into a 

 ball. The opening was on the side. Death was probably 

 caused from exposure to continued cold owing to the un- 

 protected location of the nest. 



The poor judgment shown in not building the nest 

 securely in the middle of the large sod, and other similar 

 instances of poor management, have led the writer to 

 believe that the intelligence (if that term may be used) of 

 the ZapH.s Undson'uis is of comparatively low grade, much 

 lower, for instance, than that of the deer mouse (Peromys- 

 cus Leucopus). 



The accompanying chart, which is a record of minimal 

 nightly temperatures, according to the official observa- 

 tions of the U. S. "Weather Bureau for this section (Bos- 

 ton), shows the activity of the mouse in relation to the 

 temperature during August, September, October and No- 

 vember, and brings out some rather interesting facts. For 

 example, on October 15, 16 and 17, with the minimum 

 nightly temperature 42°, 36° and 42°, respectively, the 

 mouse was active, while on September 22, 23, 24 and 25, 



