Bats of the genus concerned were given the generic name _Nycteris_ by Borkhausen in 1797 (p. 66), and the name _Lasiurus_ by Gray in 1831 (p. 38). For much of the latter part of the 19th century the generic name _Atalapha_ proposed by Rafinesque in 1814 (p. 12) was used because it antedated the name _Lasiurus_. In this period Harrison Allen (1894:137) raised to generic rank the name _Dasypterus_ that had been proposed by Peters in 1871 (p. 912) only as a subgenus for the yellow bats. Since 1894 the yellow bats ordinarily have borne the generic name _Dasypterus_. The red bats and the hoary bat continued to be referred to as of the genus _Atalapha_ until early in the 20th century when it was decided that a European bat of another genus was technically the basis for the name _Atalapha_. Thereupon _Lasiurus_ was again used in the belief that it was the earliest available name for the bats concerned. But in 1909 (p. 90) Miller showed that the name _Lasiurus_ was preoccupied by _Nycteris_ Borkhausen, 1797 (p. 66). From 1909 until 1914 in conformance with the Law of Priority _Nycteris_ was used for the red bat and the hoary bat. At this point it is desirable to digress and indicate why and how the Law of Priority came into being. In the 19th century different technical names were used for the same kind of animal depending on the opinions of individual authors. For example, one author used name A because it was most descriptive of the morphology of the animal, another author used name B because it had been used more often than any other, another author used name C because it was more euphonious, etc. In order to achieve uniformity and stability a set of rules was drawn up in 1901 at the International Zoological Congress in Berlin. Those rules were based principally on the rule, or law, of priority. In effect, the law stated that the technical name first given to a kind of animal (with starting date as of January 1, 1758, _Systema Naturae_ of Linnaeus) would be the correct and official name. After the mentioned rules were adopted, some zoologists, mostly non-taxonomists, objected to the rules and in response to these objections a compromise was adopted in 1913 at the International Zoological Congress in Monaco and the International Committee on Zoological Nomenclature was authorized to set aside, at its discretion, the Law of Priority. In 1913 it was thought by everyone that the names conserved (_nomina conservanda_) by setting aside the rules would be few.