196 Mr. O. Thomas on the South- American 
Species and subspecies :— 
altorum, All. 
aureus, Tomes, 
twops, Thos. 
cinereiventer, All, 
daphne, Thos. 
gracilis, Thos. 
hylophilus, Osg. 
ischyrus, Osg. 
kalinowsku, Thos. 
monochromos, Bangs. 
niveipes, Thos. 
notatus, Thos. 
paramorum, Thos. 
popayanus, All. 
pretor, Thos. 
princeps, Thos. 
pyrrhonotus, Thos. 
rhoadsi, Stone. 
laniger, Thos. taczanowsku, Thos. 
macconnelli, de Wint. vestitus, Thos. 
3. PH#NomMyYs, gen. nov. 
Form normal, ‘Tail short-haired. Claws slender, not 
specially curved. Mamme 2—2=8. 
Skull slender, of normal proportions. Interorbital region 
slightly concave, its edges forming definite raised beadings, 
continued backwards across the parietals. 
Incisors rather heavy. M/* not so evenly oblong as in the 
other genera, the antero-internal cusp more definitely 
reduced. 
Range. South-eastern Brazil (Bahia, Rio Janeiro). 
Genotype and only species. Phenomys ferrugineus, Thos. 
(Oryzomys ferrugineus, 'Thos.). 
4, DrLomys, gen. nov. 
Form normal. ‘Tail quite short-haired, about as in 
Oryzomys. Clawsnormal. Mammez 2—2=8 in two speci- 
mens of D. dorsalis from Rio Grande do Sul, 1—2=6 in one, 
believed to represent a new subspecies, from Rio Janeiro. 
The latter number may be an abnormality. 
Skull long, with long heavy muzzle and small brain-case. 
Tnterorbital region rather broad, smooth, its edges rounded, 
or slightly squared, not ridged or beaded. Zygomatic plate 
projected forwards above far enough to be seen from above, 
that of all the other forms mentioned in the present paper 
absolutely without projection. 
Molars rather narrow. M"* evenly oblong. 
Range. South-eastern Brazil, from Espiritu Santo to Rio 
Grande do Sul. 
Genotype. Delomys dorsalis Hens. (Hesperomys dorsalis, 
Hens.). 
Other forms :—“* Oryzomys” sublineatus, Thos, and a new 
subspecies of dorsalis described below. 
