OCHETODON. 151 
An allied species, 0. Jongicauda (Baird), is found in California, and has been recorded 
from Guatemala; but, as will be seen presently, the determination of the speci- 
mens from the latter locality is doubtless erroneous. It resembles 0. mexicanus in 
length of tail and in general coloration, but is a small species, with small hind feet 
of about 0-65 in length. 
1. Ochetodon humilis. 
Mus humilis, Bachman, Proc. Ac. Philad. 1841, p. 97 (deser. orig.)’; Audubon & Bachman, Quadr. 
N. Am. i. p. 103, pl. Ixv.’ | 
Ochetodon humilis, Coues, Proc. Ac. Philad. 1874, p. 185°; Mon. N.-Am. Rodent. p. 123%. 
Reithrodon megalotis, Baird, Mamm. N. Am. p. 451 (1857, descr. orig.)’; Rep. U.S. Mex. Bound. 
Surv. ii. Mamm. p. 43°. 
Hab. Nortu America, from Iowa southwards 4.—Mexico, Sonora (Kennerly, U.S. Nat. 
Mus.*), “ South Mexico” (Sallé, Mus. Brit.). 
Two specimens, obtained by the naturalists of the Mexican Boundary Survey 
between Janos and San-Luis Spring in Sonora, were considered by Professor Baird to 
differ from the known species of groove-toothed Mice, and were made the types of his 
Reithrodon megalotis®. Dr. Coues, however, has no hesitation in identifying them 
with the present species, remarking that the height of the ear is not greater than 
occurs in typical O. humilis, and that only one of the specimens is larger than United- 
States examples. He adds that “it is interesting to observe that these two animals do 
not approximate towards either O. longicauda or the still larger and longer-tailed 
O. mexicanus’’*. 
According to Audubon and Bachman this little Mouse inhabits grass-fields and 
plantations in the southern States, and constructs nests of soft grasses, which are either 
placed under brush-heaps and fences or among long grass. They will breed in captivity, 
and are very gentle in disposition. 
There are two specimens in the British Museum received from Sallé, one of which 
is marked “‘S. Mexico ;” the label of the other is illegible. 
2. Ochetodon mexicanus. 
Mus tazamaca, Gray, P. Z.S. 1848, p. 79 (sine descr.)’. 
Reithrodon mexicanus, de Saussure, Rev. et Mag. Zool. 1860, p. 109 (descr. orig.) *; Tomes, 
P. Z. S. 1861, p. 284°. | 
Ochetodon mexicanus, Coues, Proc. Ac. Philad. 1874, p. 186*; Mon. N.-Am. Rodent. p. 128° ; 
Alston, P. Z. S. 1876, p. 756°; op. cit. 1877, p. 446". 
Reithrodon sumichrasti, de Saussure, Rev. et Mag. Zool. 1861, p. 3 (descr. orig.)*. 
? Reithrodon longicauda, Tomes, P. Z.S. 1861, p. 284 (nec Baird ?)’. 
Hab. Norra America, Louisiana ®.—Mexico (Sallé, Mus. Brit.), Vera Cruz (de Saus- 
sure”), Tehuacan, Orizaba, Cordova (Sumichrast, U.S. Nat. Mus.®), Mirador 
(Sartorius, ib.5) ; GuaremaLa, Coban (Mus. Brit.1°), Dueiias (Salvin, ib.*). 
