On the testimony of a friend who had previously obtained several specimens for him, Swenk (1926:321) records the least weasel from Oshkosh, Garden County, Nebraska, which is a marginal record of occurrence to the southwest for _M. r. campestris_. At an early stage in the study of American weasels the writer examined the specimens from Nebraska saved by Mr. Myron H. Swenk and recorded measurements of them. However, at the time of writing this account the specimens were not available for examination and the account of coloration is accordingly incomplete. The large size, particularly the large external measurements, comprises the principal distinguishing character of this subspecies of the least weasel. Of the four adults examined from Iowa and South Dakota one exhibits lesions such as result from infestation of the frontal sinuses by nematodes. _Specimens examined._--Total number, 21 as follows. Arranged alphabetically by states and by counties, from north to south in each state. Unless otherwise indicated, specimens are in the United States National Museum. =Iowa.= _Howard County_: Chester, 1[12]. _Palo Alto County_: Emmetsburg, 1[65]. _Kassuth County_; Algona, 1[65]. _Clayton County_: National, 1. _Storey County_: Nevada, 1[65]. _Wapello County_: Ottumwa, 1[65]. _Henry County_: Mount Pleasant, 1[66]. =Nebraska.= _Holt County_: Page, 1[35]. _Madison County_: Norfolk 1[35]. _Cuming County_: Beemer, 1. _Hamilton County_: Chapman, 1[35]. _Clay County_: Inland to 1 mi. east thereof, 7[35]. =South Dakota.= _Brown County_: shore of Sand Lake, S. 15 T. 126N, R. 62W, 1. _Day County_: Waubay Migratory Waterfowl Refuge, 1. _McCook County_: Salem, 1[102]. =MUSTELA FRENATA= Lichtenstein Long-tailed Weasel (Synonymy under subspecies) _Type._--_Mustela frenata_ Lichtenstein, Darstellung neuer oder wenig bekannter Säugethiere, pl. 42 and corresponding text unpaged. 1832. _Range._--From southern Canada southward over all of the United States, México, Central America, Venezuela, and the republics of western South America to southern Perú and extreme northern Bolivia. All the life-zones from Alpine Arctic to Tropical are inhabited. In the extremely desert region of southeastern California and western Arizona the species is scarce or possibly absent although recovery of a skull (see under account of _M. f. neomexicana_) from near the center of this region at Potholes on the Colorado River, and a reported occurrence in the mountains of Baja California, México, indicate that a few individuals of the species live in favorable habitat even in this desert region.