HABITS OF THE THREE SUBGENERA STUDIED 9 



running through the branches, and I have shot many speci- 

 mens in such situations. Certainly this subgenus exhibits 

 tendencies which are more arboreal than those of any other 

 wood rat within the United States. 



The food staple of this animal under the above conditions 

 seems to be seeds, pinyon nuts and acorns, shrub seeds and 

 berries in season. It is also known that another subspecies 

 is very partial to certain fungi (see Parks, 1922). It prob- 

 ably indulges in considerable insect food, and meat when 

 available; but when necessary it can supplement a dwindling 

 larder with more bulky items, such as bark or fibrous roots. 

 Its fare, in fact, is probably as concentrated as a rodent of 

 its type could be expected to be. 



Neotoma {Neotoma) alhigula alhigula Hartley is one of a 

 well-defined group of its subgenus. It is a resident of the 

 Upper and Lower Sonoran zones of the Arizona, New Mexico 

 and northern Mexico desert areas. It may be found in any 

 situation where subsoil moisture conditions favor a moderate 

 growth of shrubby plants and scattered trees, such as the 

 borders of a "wash" of a foothill canyon. It usually builds a 

 nest of respectable dimensions, or it may occupy a cranny 

 in a rocky outcrop. I have known it to seek safety in the 

 hollow trunk of a tree, but never among the upper branches. 

 It may be presumed to climb thither, however, in search of 

 such berries as the elder. 



The chief food item of this form is also seeds and berries. 

 It often gnaws cacti, undoubtedly for the moisture content, 

 and for the same reason, may be presumed to consume any 

 succulent vegetation available. Due to the cHmatic exigen- 

 cies of its environment it seems probable that this animal is 

 obliged to consume a greater proportion of roughage, from 

 time to time, than is Homodontomys; but this is largely 

 conjecture. 



Neotoma (Teonoma) cinerea dnerea (Ord), with its sub- 

 species, is the ''pack rat" of the western mountains. At 



