PEROGNATHUS. 165 
3. P. fasciatus. Upper parts “light sandy yellowish, closely lined throughout 
with black ;” lower parts and limbs white; a salmon-coloured stripe along the 
flanks. Length of head and body about 4":25, of tail considerably less. 
The other three species (P. parvus, Baird, P. monticola, Baird, and P. penicillata, 
Woodhouse) are all found in California, and very possibly cross our northern frontier. 
But the only other species which has yet been recorded from Central America is the 
P. bicolor of Gray, which, as I have shown elsewhere, is neither a Perognathus nor a 
native of the subregion *. 
1. Perognathus flavus. 
Perognathus flavus, Baird, Proc. Ac. Philad. 1855, p. 332 (deser. orig.)'; Mamm. N. Am. p. 423°; 
Rep. U.S. Mex. Bound. Surv. ii. Mamm. p. 42°. 
Cricetodipus flavus, Coues, Proc. Ac. Philad. 1875, p. 300*; Mon. N.-Am. Rodent. p. 516°. 
Hab. Norra America, central regions, from the Dominion of Canada southwards®.— 
Mexico, Chihuahua (Web, U.S. Nat. Mus.3), Matamoras (i0.°). 
Although rare in collections, this diminutive Pocket-Mouse was found by the officers 
of the United-States Boundary Survey to be “ quite abundant throughout the west, from 
the lower Rio Grande to El Paso, and a considerable distance westward”?, According 
to Dr. Coues, its range is a tolerably extensive one, extending southwards from 49° north 
latitude throughout the Rocky-Mountain and Middle-Faunal Provinces of North 
America to the more northern States of Mexico. On the Pacific slopes it is replaced by 
P. parvus (Baird), which apparently only differs in having the tail and hind feet longer, 
and may very probably prove to be merely a geographical race of P. flavus. 
2. Perognathus hispidus. 
Perognathus hispidus, Baird, Mamm. N. Am. p. 421 (1857, descr. orig.) ; Rep. U.S. Mex. Bound. 
Surv. ii. Mamm. p. 42*; Coues, Proc. Ac. Philad. 1875, p. 296°; Mon. N.-Am. Rodent. 
p-. 513%. 
Hab. Mexico, Charco Escondido, Matamoras (Couch, U.S. Nat. Mus.)}. 
Nothing whatever has been added to our knowledge of this animal since its first 
description, the two type specimens obtained by Lieutenant Couch being still the only 
ones known. 
* Of. Ann. & Mag. Nat. Hist. 5th series, vi. pp. 118, 119; where I have redescribed the type specimens 
under the name of Heteromys bicolor, and shown that they were sent to the British Museum by Dyson from 
Venezuela, and not (as stated by Gray) by Sallé from Honduras. 
