2 BULLETIN 57, UNITED STATES NATIONAL MUSEUM. 



species, 80 genera, and 14 families and subfamilies. As might have 

 been anticipated, this work, the only complete special monograph of 

 the order, was such a stimulus to the study of bats that since it 

 appeared these animals have received more attention than ever before. 

 In 1904 Trouessart recorded no less than 851 species, 122 genera, and 

 18 families and subfamilies. It appears, however, that even these 

 numbers are much too small. Detailed study of the skeleton, par- 

 ticularly of the wing and shoulder girdle and of the structure of the 

 tooth cusps, leads me to the conclusion that among the known species 

 at least 173 genera and 36 families and subfamilies should be recog- 

 nized. With regard to the species, recent work " shows that an enor- 

 mous increase is to be expected as the characters on which distinc- 

 tions are based come to be better understood. It seems highly prob- 

 able that the total number of recognized bats will eventually exceed 

 2,000 named forms. 



HISTORY. 



The following summaries are intended to give somewhat in detail 

 the more important facts in the development of the classification of 

 bats. The list, though incomplete, gives a sufficiently clear idea of 

 the course that this work has followed. 



1758.' Linnaeus, Systema Naturae, I, 10th ed. Vespertilio, the only 

 genus of bats recognized, appears as the fourth genus of Primates 

 (p. 31.) The other genera are Homo, Simla, and Lemur. In the 

 twelfth edition, 1766, Noctilio is separated from Vespertilio and 

 placed among the Glires. This is apparently the only instance of 

 one genus of bats being referred to a different order from the others. 

 1772. Briinnich, Zoologia Fundamenta. Vespertilio is here one of 

 the genera of Ferae; the others are Hystrix, Lepus, Gavia, Castor, 

 Mus, Sciurus, Etinaceus, Sorex, Phoca, Lutra, Hyaena, Felis, Canis, 

 Cercopithecus, and Lemur. The orders recognized are : Bruta, Ferae, 

 Pecora, Bellua, and Cetacea. 



1777. Scopoli, Introductio ad Historiam Naturalem. The genus 

 Vespertilio is placed between Bradypus and Lemur in the Ungui- 

 culata. The position of this order in the system is as follows : 

 Tribus XII. Mammalia. 

 Gens I. Cetacea. 

 Gens II. Quadrupedia. 

 Divisio I. Aquatilia. 

 Divisio II. Terrestria. 

 Ordo I. Ungulata. 

 Ordo II. Unguiculata. 



a See especially the papers (Proc. Zool. Soc. London, 1905, II, pp. 75-145, 

 October 17, 1905, and Ann. Mag. Nat. Hist., 7th ser., XVI, pp. 648-662, December, 

 1905) by Mr. Knud Andersen on the Old World leaf -nosed groups. 



