John Kirk Townsend introduced the Oregon Junco to science as
Fringilla oregana, but since 1856 it has been classified in the genus Junco as Junco oreganus, Junco oregonus, Junco hyemalis oreganus or Junco hyemalis oregonus. The change of spelling to oregonus is not justified under the current International Code of Zoological Nomenclature, and since 1901 oreganus has been used universally. Under the code’s articles 31 and 34 adjectival species-group names (both species and subspecies) must agree in grammatical gender with the genus with which they are combined. Under Article 30, Junco is masculine, whereas Fringilla is feminine. If oregana is an adjective, as it has generally been construed, it needed to be changed to oreganus to agree with Junco. But the termination “-a” is ambiguous, and in ambiguous cases the code prescribes that the word be construed as a noun in apposition that remains unchanged regardless of the gender of the genus in which the species or subspecies is classified. This case parallels other similar examples that have been treated inconsistently in recent literature. A comprehensive review of such cases at the level of both species and subspecies is needed.