RODENTIA MURINAE HESPEROMYS COGNATUS. 



469 



HESPEROMYS GOSSYPINUS, Leconte. ' 



Cotton Mouse. 



Hesperomys gossypinus, LECONTE, Pr. A. N. Sc. Phila. VI, Oct. 1853, 411. 

 Ilypudaeux gossypinus, LECONTE, M. Murtries Cuvier, I. 1831. App. (No. desc.) 



SP. CH. Larger than H. leucopus. Tail considerably shorter than the head and body ; above, rusty yellowish brown, 

 brightest on cheeks, a dorsal wash of darker. Beneath, ashy white. Tail scarcely, if at all, lighter below than above. 

 Hind foot from heel ,90. 



In size this animal considerably exceeds the specimen described of H. cognatus, though the 

 essential characters appear the same. The ears are large and thin ; higher than broad ; entirely 

 dusky. The upper parts are of rather a rusty yellowish brown, the median portion of the back 

 darker. The under parts are dull ashy white ; the feet are grayish white. The tail is brown 

 above, passing beneath into a dark ashy brown, little, and in one specimen not at all, different 

 from the upper part. The dull brownish rusty on the cheek is more clear than elsewhere. 



I am hardly satisfied that this animal is different from the smaller H. cognatus, as the 

 difference in size is no greater than is to be seen in series of Hesperomys from more 

 northern localities. The tail is still duskier beneath than in H. cognatus, and the sides more 

 rusty ; otherwise, I can realize only the larger size. Should both prove to be the same, the 

 name H. gossypinus must, of course, take precedence. 



There is every reason to consider this mouse as specifically distinct from H. leucopus of the 

 north; although skins, when much stretched, (as Nos. 1105, 1112, from Middleboro', Massa 

 chusetts,) of the latter, may measure as much as those recorded here, yet they are certainly 

 actually smaller, as shown by the feet, which never attain anything of the length of .45 for 

 the anterior and .90 for the posterior. 



List of specimens. 



HESPEROMYS COGNATUS, Leconte. 



? Hesperomys polianotus, WAGNER, Wiegmann's Archiv. 1843, u, 52. (Georgia.) 

 Hesperomys cognatus, LECONTE, Pr. Phila. Acad. Nat. Sciences, VII, Dec. 1855, 442. 



SP. CH. Smaller than H. leucopus. Tail considerably shorter than head and body. Young, slaty plumbeous. Adult, 

 yellowish brown, with a dorsal wash of darker. Under parts and feet soiled white or light ashy. Under surface of tail, 

 ash gray, not conspicuously different from the dorsal color. Ears without hoary edging. 



This species is a very near relative of the Hesperomys leucopus of the north, but differs by 

 quite appreciable characters. In size it is considerably inferior to the last mentioned species, 



