190 PROCEEDINGS: BOSTON SOCIETY NATURAL HISTORY. 
form at Flamingo and twelve at Cape Sable. In this series there 
are many young of various ages, and these show the difference in 
color that separates 0 . coloratus from 0 . natator quite as strongly 
as do the adults. 
Oryzomys palustris coloratus is the extreme form of the palustris 
series, both in color and size. It occupies only the southern, tropi¬ 
cal part of the Florida peninsula. A series of Oryzomys from Oak 
Lodge, while referable to natator , shows an approach to the more 
southern form, both in size and color. 
Average measurements of old adult specimens of Oryzomys. 
Name. 
Locality. 
No. in 
aver. 
Total 
length. 
Tail 
vert. 
Hind foot. 
0. palustris 
N. C., Raleigh. 
3 
235. 
114.33 
28.33 
0. palustris 
Ga., Ossabaw Isl. 
7 
255.58 
116.14 
30.14 
0. palustris 
Ga., St. Mary’s 
7 
252. 
117. 
29.57 
0. palustris 
Fla., Burnside Beach. 
4 
266.25 
122.75 
29.5 
0. palustris 
La., Burbridge. 
9 
246.22 
124. 
29.72 
0. texensis 1 
Tex., Rockport. 
7 
264. 
132. 
30. 
0. natator 
Fla., Gainesville. 
4 
287.75 
149.25 
34.12 
0. natator 
Ela., Oak Lodge. 
6 
293.66 
144.66 
33.66 
0. coloratus 
Fla., Cape Sable. 
Q 
O 
301.06 
148.2 
34.93 
0. coloratus 
Fla., Flamingo. 
6 
303.86 
152.5 
34.7 
Sigmodon hispidus hispidus Say and Ord. 
\ 
Sigmodon hispidus Say and Ord, Jour. acad. nat. sci. Phila., 
1825, vol. 4, p. 354. 
Type locality. St. John’s River, Florida (probably in the 
vicinity of Jacksonville) . 2 
The brown northern form of the cotton rat has a wide distribu¬ 
tion extending in its extreme form from North Carolina south to 
eastern Georgia and west to Louisiana. Specimens from St. Mary’s 
and Cumberland Island, Georgia, and the region about the type 
1 Measurements from Allen, Bull. Amer. mus. nat. hist., 1894, vol. C, p. 177. 
2 The cotton rat was named from as unfortunate a region, from a systematic point of 
view, as it is possible to choose, as specimens from the St. John's River, Fla., are exactly 
intermediate between the brown northern form and the dark-colored'form of eastern 
Florida. As Mr. Chapman has named the dark form from southeastern Florida (sub¬ 
species littoralis), I shall therefore be understood to mean the brown northern form 
when I speak of subspecies hispidus. 
