14 
LORQUINIA 
Since that reference, many new species have been discovered by 
the various zoologists. Today the genus Neotoma is divided into sev- 
eral sub-genera, Neotoma, Homodontomys and Teonoma. The sub- 
genus Neotoma, containing 56 species and sub-species, is readily divis- 
ible into six rather well marked, yet closely related groups. 
The genus Neotoma is restricted to North America. It reaches 
from ocean to ocean in the latitude of the lower Mississippi, but the 
species are most numerous along the backbone of the continent from 
Nicaragua and Guatemala northward through Mexico and the south- 
western United States. The species and subspecies are usually limited 
to one or two life zones, but sometimes groups of closely related forms 
extend throughout several zones. 
The habits of the various species are very similar, but they may 
vary considerably in the same species according to the environments. 
Most of the rats prefer rocky ledges and crevices for their homes ; 
some pile up sticks and leaves making a large conical nest under oak 
trees or bushes, usually on sloping ground. The rats that prefer these 
nests often build a nest in the same tree which shades their big nest 
on the groun^k These big nests contain many chambers and runways, 
some of which run into the ground under the nest. On the desert 
plains the wood rats' nests are composed of a prickly mass of cactus 
and thorns. It is wonderful how they can live in them comfortably. 
During the night the wood rats come out of their nests and scout 
around for food. Some of the rats cannot wait for it to get dark, but 
come out along toward dusk and scamper about. They are strictly 
vegetarian and feed on cactus, fruits, leaves and other greens. 
The wood rat that I know best is the "Large Eared Wood Rat" 
(Neotoma fnscipes maerotiis Thomas). This rat is found in the upper 
Sonoran and lower Transition zones in the San Diegan district north- 
west of the Mexican line, including also the narrow coast strip farther 
northward, even to Monterey. In the San Gabriel Wash, near the 
Foothill Boulevard, this large-eared rat is very abundant. Its nests, 
built in clumps of cactus, are constructed of sticks and rubbish of all 
sorts, including the dead parts of cacti. Any one unfamiliar with these 
rats would at first perhaps not observe their nest at all. When once 
discovered they are very noticeable, with their many runways through 
the grasses. In size these rats are about the same as the regular old 
brown rat, with which every one is familiar. The average length is 
about 357 mm., tail vertebrae, 170 mm., hind foot, 37 mm. 
Their color in a fresh pelage is of a grayish brown, sometimes with 
an ochraceous buff mixed in. On the face and sides this color becomes 
much lighter. The black-tipped hairs darken the back and give it a 
grizzled effect. The under surface is white with a pale buff on the 
belly. The front feet are white, as are also the hind feet, except for a 
little dusky coloring. The dorsal surface of the tail is a brownish 
black ; the under part is whitish. 
