MAMMALS OF MINNESOTA. pal We 
_An acquaintance of mine after this tells me that his Indian, in 
this way repeatedly called the musquash within reach of his 
paddle in the moonlight, and struck at them.”—Thoreau. The 
Maine Woods, p. 211. 
Fammy DIPODID. 
This is an interesting, though not a large, family containing 
five genera of springing mice distributed over widely separated 
regions of the earth. The three subdivisions included under 
this head are so diverse that there is considerable difference of 
opinion as to their relative rank. The affinities assumed for 
the animals included in them are borne out by external resem- 
blances more fully than by anatomical structure. Alston gives 
the following diagnosis of the family: ‘‘ Incisors compressed. 
Premolars present or absent. Grinding teeth rooted or root- 
less, not tubearculate, with more or fewer transverse enamel-. 
folds. Skull with the brain-case short and broad, infraorbital 
opening rounded (often as large as the orbit); zygomatic arch 
slender; curved downward ; the malar ascending in front to the 
lachrymal in a flattened perpendicular plate ; facial surface of 
the maxillaries minutely perforated; mastoid portion of the 
auditory bullz usually greatly developed. Metatarsal bones 
greatly elongated, often fused into a cannon-bone. Form slen- 
der ; front portion of the body and fore limbs very small ; hind 
limbs long and strong, with from three to five digits; tail 
long, hairy.” 
Three subfamilies, viz: (Jaculine=) 1. Zapodine, 2. Dipo- 
dince, and 3. Pedetine. The last named departs most from the 
murine or mouse-like character, and contains a single genus 
and species found in South Africa. The animal is figured at 
the left in the headpiece to Rodentia. It is of nearly the size 
of a rabbit, and but for the long and densely hairy tail, would 
much resemble one. The fore feet are rather larger than those 
of allied forms, while the nails upon the posterior extremities 
are almost hoofs. The cervical vertebrz are free as are the 
metatarsals. 
The Dipodine form three genera, Dipus, Alactaga and Platy- 
cercomys. 
The first named genus contains the jumping mice of. Hurope 
and northern Africa, while the second inhabits the steppes of 
Asia and European Russia. These animals have the cervicals 
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