AprRIL, 1914. MAMMALS OF NORTHERN PERU — Oscoop 155 
climate humid.* The probability is great, therefore, that our speci- 
mens from Tambo Almirante represent true O. stolzmannt, and since 
the type is imperfect and not fairly comparable with modern specimens, 
it becomes practically necessary to regard them as that species. A 
large series from Moyobamba seems referable to the same species, 
although averaging paler and including some specimens with somewhat 
whitish under parts. This paleness is perhaps ontogenetic and may 
be due to the fact that nearly all the specimens from Moyobamba were 
taken about houses and gardens in the town rather than in the adjoin- 
ing forest. The published measurements of the type of stolzmannt 
indicate an animal slightly larger than the average in our series, but 
there is at least one unusually large example among those from Moyo- 
bamba which nearly equals it. 
The specimens from Tambo Almirante have clear ochraceous buff 
under parts, lighter toward the chin. The upper parts are somewhat 
darker and with many fine lines of dusky. Average measurements of 
four adults are: Total length 214 (205-224); head and body 94 (91-96); 
tail 120 (111-128); hind foot 23.9 (23.5-24.5). 
Oryzomys stolzmanni maranonicus subsp. nov. 
Type from Hacienda Limon, near Balsas, Marafion River, Peru. 
No. 19449 Field Museum of Natural History. Male adult. Collected 
May 7, 1912, by W. H. Osgood and M. P. Anderson. 
Characters.— Similar to Oryzomys stolemanni but paler and having 
nearly white under parts sharply distinguished from the upper parts. 
Ground color of upper parts nearly ochraceous with a fine linear mixture 
of dusky; sides more nearly pure ochraceous; head and face scarcely 
different from body; under parts soiled whitish, sharply defined, the 
hairs with slaty bases; feet white; tail above dusky, below whitish for 
the proximal half, and thence gradually darker to the tip. 
Skull practically as in stolzmannt, although in the type the brain- 
case is deeper and more arched. 
Measurements.— Type: Total length 215; head:and body 92; tail 
123; hind foot 24; ear from notch (dry) 14. Skull of type: Basilar 
length 17.4; zygomatic width 12.6; interorbital constriction 3.8; width 
*The following description of Huambo, from Stolzmann’s notes, is given by 
Taczanowski (P. Z. S., p. 4, 1882): ‘‘Huambo. 3,700 pieds de altitude. Plantation 
inhabiteé au fond de la forét vierge, A 10 kilometres de Chirimoto, au bord de la 
riviére Huambo, qui, comme on le pretend, se rend prés de Pachiza au fleuve de 
Huallaga. C’est une forét chaude et humide, du caractére des foréts vierges.”’ 
