1897] NATURAL SCIENCES OF PHILADELPHIA. 213 



It is found in all wooded parts of the State, at all altitudes ; its range 

 somewhat overlapping that of P. canadensis in the borders of the 

 denser evergreen forests of the northern coiiDties. As in the cases 

 already cited under Mierotw pennsylvanicus there is a strong tend- 

 ency in the Deer Mice of the Juniata river watershed to assume a 

 darker, deeper shade of brown than the normal colors seen in eastern 

 specimens. 



18. Peromyscus canadensis (Miller). Canadian Deer Mouse. 



Four typical specimens of this distinct species were taken in the 

 primeval forest about two miles from Eaglesmere. They were not 

 found in a similar forest in Clinton County, leueopus only being 

 taken there. It is likely that typical canadensis is not found in 

 Pennsylvania except along its northern border, in the most boreal 

 environments of the mountain tops in isolated localities. Along the 

 culminating ridge, southward, it intergrades into the following sub- 

 species, inhabiting the loftier summits of the southern Alleghenies. 



19. Peromyscus canadensis nubiterrae (Rhoads). 5 Cloudland Deer Mouse. 



Of great interest, as showing the true relationships of the long- 

 tailed, dusky deer mouse of the balsam forests of Tennessee and 

 North Carolina, is a series of 29 Peromyscus taken in Cambria and 

 Somerset Counties, Pennsylvania, by Mr. Ingersoll. Nine of these 

 were trapped at Kring's Station, the remainder at Summit Mills. In 

 size and proportions these are conclusively connectant between the 

 large form found in Canada and New England and the diminutive 

 cloud-dweller of the Great Smoky Mountains. In color the Penn- 

 sylvania series shows a marked tendency to assume the dark brown 

 shades of the upper parts, which distinguish nubiterrcB from the 

 ochraceus gray of canadensis. The wide, dark dorsal area charac- 

 teristic of Roan Mountain specimens is also apparent in those from 

 Somerset County, but the pencil of white hairs at the anterior base 

 of ear in canadensis, absent in nubiterrce, is retained by all in the 

 series taken by Mr. Ingersoll. 



An average of four of the larger adults of canadensis from Peter- 

 boro, New York, recorded by Mr. Miller, gives the following measure- 

 ments in millimeters: total length, 190; tail vertebrae, 99 ; hind 

 foot, 21.5. Similar measurements of four specimens from Somerset 

 County are : total length, 180 ; tail vertebrae, 91 ; hind foot, 22 ; 

 while those of nubiterrce respectively are 167, 86 and 21.5. The 



5 P. leucopus nubiterrse Rhoads; Proc. Acad. N. Sci., Phila., 1896, p. 187. 

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