A third species, Atalapha egregia, allegedly allied to the small yellow bat, L. ega, was named in 1871 (p. 912) by Peters from Santa Catarina, Brazil, but Handley (1960:473) thinks that L. egregius is allied instead to the red bats. The species L. egregius has not been studied in connection with the observations reported below.
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.
Returning now to the generic names applied to the bats concerned, it is to be noted that from 1803 until 1909 Nycteris had been used as the generic name of an African bat on the erroneous assumption that the name was first applied in a valid fashion to the African bat. With the aim of conserving the name Nycteris for the African bat, some zoologists petitioned the International Committee on Zoological Nomenclature to set aside the Law of Priority and petitioned also that the name Lasiurus be validated for use again as the generic name for New World bats. This petition was granted in 1914 in the first lot of names for which exception to the rules was made. As a result, since 1914 Lasiurus has been used with increasing frequency, and Nycteris with decreasing frequency, for New World bats.
The above explanation of the application of the generic names Nycteris, Atalapha, and Lasiurus is given for two reasons: First, study of more abundant material than was available to Harrison Allen in 1894 when he raised Dasypterus to generic rank reveals, as set forth beyond, that the yellow bats are not generically different from the red bats and hoary bat and so will bear the same generic name that is applied to the red bat and hoary bat; second, a choice of generic names has to be made. Actually, the International Commission on Zoological Nomenclature since 1913 has voted to make many, instead of only a few, exceptions to the rules. The number of names resulting from these exceptions is becoming so large that some zoologists fear that the chaotic condition of nomenclature in the previous century will return. Those who hold such fears maintain that adherence to the rules of 1901, or to the Law of Priority, or at least to some rules, clearly is desirable. Certainly there is much logic in that view. According to the rules, Nycteris is the correct name of the bats concerned. According to the Commission, it is well to use instead the name Lasiurus. Perhaps the time has come to follow the rules and use Nycteris. But, because of the possibility that the Commission will return to its policy of 1913 and recommend only a few instead of many exceptions to the rules, the generic name Lasiurus is tentatively used in the following accounts.
Genus Lasiurus Gray
Hairy-tailed Bats
| 1797. | Nycteris B[orkhause]n, Der Zoologe (Compendiose Bibliothek gemeinnützigsten Kenntnisse für alle Stände, pt. 21), Heft 4-7, p. 66. Type, Vespertilio borealis Müller [= Lasiurus borealis]. Nycteris Borkhausen is a homonym of Nycteris G. Cuvier and É. Geoffroy St.-Hilaire, 1795, type Vespertilio hispidus Schreber, 1774 [= Nycteris hispida], from Senegal. Although Nycteris Cuvier and Geoffroy St.-Hilaire is a nomen nudum, Opinion 111 of the International Commission of Zoological Nomenclature establishes the name as available for a genus of Old World bats. On this basis, Nycteris Borkhausen is not available for the New World genus. Nycteris É. Geoffroy St.-Hilaire, 1803, is a synonym of Nycteris Cuvier and Geoffroy St.-Hilaire, 1795, as given status by the Commission. |
| 1831. | Lasiurus Gray, Zool. Misc., No. 1, p. 38. Type, Vespertilio borealis Müller. |
| 1871. | Atalapha Peters, Monatsber. K. Preuss. Akad. Wiss., Berlin, p. 907, and other authors [nec Atalapha Rafinesque, 1814]. |
Type species.—Vespertilio borealis Müller.
Diagnosis.—Interfemoral membrane large and most of its upper surface furred; mammae 4; third, fourth and fifth fingers progressively shortened; ear short and rounded; skull short and broad; nares and palatal emargination wide and shallow (width transversely exceeding length anteroposteriorly); sternum prominently keeled; i. 1/3, c. 1/1, p. 1/2 or 2/2, m. 3/3; when two upper premolars present, anterior one minute, peglike, and displaced lingually; M3 much reduced, area of its crown less than a third that of M1.