CASTORID.E— CASTOR— CASTOR FIBER. 437 



RELATION OF THE AMERICAN AND OLD WORLD BEAVERS. 



The earlier, and by far the greater part of naturalists have regarded the 

 Beavers of the Old World and the New as specifically identical. According to 

 Brandt,* Oken,t in 1816, first suggested that they were different ; he regarding 

 the American animal as being more reddish and much the larger. G. Cuvier, J 

 in 1817, affirmed, that, after the most scrupulous comparison of the Old 

 World Beaver, from different localities, with the New World Beaver, he was 

 unable to satisfy himself whether or not they were specifically distinct. In 

 1820, Kuhl§ described a young specimen of the American Beaver from Hud- 

 son's Bay, under the name Castor canadensis, without, however, giving any 

 special reasons therefor. In 1825, F. Cuvier, || in describing specimens of 

 the European Beaver, claimed that there were very decided differences in the 

 structure of the skull as well as in size, he stating the European Beaver to be 

 "d'un sixieme plus grand i|u'un Castor du Canada". His detailed account of 

 the cranial differences, however, show that his American skull was that of a 

 quite immature animal, and that the differences mentioned were mainly such 

 as would result from differences of age. He calls attention, however, to one 

 point of some importance, and one which all subsequent comparisons have 

 confirmed, namely, the greater posterior extension of the nasal bones in the 

 European animal. Gr. Cuvier,H the same year, also dwells upon the impor- 

 tance of the same character as distinctive of the two forms, as well as also 

 upon the general form of the nasal bones. In 1827, Brandt and Katzeburg** 

 pointed out numerous minor differences in the shape of the head, tail, feet, 

 incisors, etc., as existing between the single individuals compared. Richard- 

 son, ff in 1829, called the American Beaver Castor fiber, americanus, but 

 cited no differences characterizing the two forms. Keyserling and Blasius %\ 

 treated the European Beaver as sjjecifically distinct from the American, and 

 Wagner, §§ in 1844, as varietally distinct. Audubon and Bachman, || || in 1846, 

 also formally adopted the same view, but stated that the only difference per- 



M^m. Acad. St. Pdtersb., 6th ser., vol. vii, p. 44. 

 tLeiirb. il. Zuologie, 2te Alith., \*. H60. 

 t Regno Anim., 1st ed., tome i, p. 191. 

 § Beitriige zur Zoologie, p. 64. 

 || Hist. Nut. dts Mam., liv. 51. 

 IT Ossem. Foss., 3d ed., tome v, p. 57. 

 **M» •dizimscbe Zoologie, vol. i, pp. 13-30. 

 tt Faun. Bor.-Amer., vol. i, p. 105. 

 tt Wirbelthiere des Europas, p. 7. 



$§ Abbandl. d. Muocbener Akad., math.-pbys. Clause, 1844, p. 36 ; Snppl. Schreber's Saoget., iv, 7. 

 IHI Quad. N. Amer.. vol. i, p. 347. 



