_=Sorex oreopolus emarginatus=_ Jackson.--A first-year female _Sorex_, KU 54346, obtained by Rollin H. Baker from 7 mi. SW Las Adjuntas, 8900 ft., Durango, seems closest, among Mexican shrews that I have examined, to two specimens of _S. emarginatus_ from Plateado, 7600 to 8500 ft., Zacatecas. Measurements of the Las Adjuntas specimen are: total length, 88; tail, 39; hind foot, 13; palatal length, 7.2; maxillary tooth-row, 6.4; maxillary breadth, 4.9; least interorbital breadth, 3.6. _Sorex emarginatus_ previously was known only from Plateado and the type locality, Bolanos, Jalisco. Comparison of these three specimens with specimens of other species of Mexican shrews of the _S. saussurei_ group leads me to conclude that the group contains two species rather than four as was previously thought. _Sorex emarginatus_, _S. ventralis_, and _S. oreopolus_ seem to me to be conspecific. All three nominal species are relatively small, short-tailed shrews. The skulls of the three kinds resemble one another in relatively short rostrum and in dental details. Slight differences in cranial proportions differentiate the three and they should, until more specimens of each are obtained and studied, retain subspecific rank. The specific name, _Sorex oreopolus_ Merriam 1892, should apply to the three kinds since it antedates the names _ventralis_ and _emarginatus_. The two names last given, therefore, should stand as _Sorex oreopolus ventralis_ Merriam and _Sorex oreopolus emarginatus_ Jackson. The two species, the large _S. saussurei_, and the small _S. oreopolus_, as the latter is here understood, occur together over an extensive region in southern Mexico. In other parts of North America a large and a small species of _Sorex_ often occur together in a given area. The Las Adjuntas specimen was taken only 10 miles southwest of El Salto, Durango, the type locality of _S. durangae_ Jackson. Jackson (1928:101) placed _durangae_ in the _Sorex vagrans-obscurus_ species group, but the two specimens available to him were second year adults with the teeth so much worn that diagnostic characters are not visible on them. I have examined these two specimens (United States Biological Surveys Collection 94539 and 94540) and find that in bodily and cranial proportions they resemble _Sorex s. saussurei_, and I so assign them.