THE HEAVER. . 9S 



the British islands, where there is historical evidence of its former existence, besides the skulls 

 and bones which have been found in various places, but especially in the Fen lands. At present the 

 animal appears to be completely exterminated in the southern parts of Europe from France south- 

 wards, with the exception of a small colony on the Rhone, which we believe is still in existence ; and 

 only a very few individuals survive in Germany, where they are found on a tributary of the Elbe y 

 and in one or two other places. In some parts of Poland, Russia, and Austria, and in the Scan- 

 dinavian peninsula, they still, to a greater or less extent, hold their ground ; and in Asia they abound 

 about the rivers of Siberia, and in the streams which flow into the Caspian Sea. In North America 

 Beavers formerly abounded from Texas, and, according to manuscript evidence cited by Mr. Allen, 

 even from Mexico, northward to the extreme limit of forest growth, and from the Atlantic to the- 

 Pacific coast. The constant pursuit to which the animals were subjected, in consequence of the- 

 demand for their skins, greatly diminished their numbers, and in many localities altogether 

 exterminated them ; but they still occur over a very large extent of the North American continent, 

 especially in the western territories, where they are even abundant in some of the wilder parts. 



In the preceding statements we have spoken of the Beaver as forming a single species ; but it 

 has long been a moot question with zoologists whether the Beavers of the Old and New Worlds were 

 or were not specifically identical. The external differences are very slight, and those observed in the 

 skull, upon which most stress has been laid, do not appear to be of sufficient importanc3 for the 

 separation of the animals as distinct species. They consist chiefly in the greater breadth of the 

 anterior portion of the skull, including the inter-orbital space; the extension farther back of the nasal 

 bones, the greater size and depth of the basilar cavity and the moi-e anterior position of the auditory 

 bulke, in the European Beaver ; but the examination of large series of specimens has proved that 

 the skulls from both hemispheres present many exceptions, in which one or more of the peculiarities 

 which they ought to exhibit do not occur : a circumstance which of necessity greatly invalidates the- 

 distinction founded upon such characters. Dr. Ely sums up the results of an extended investigation 

 in the following words : " The extremes of difference, in their aggregate, on the one side and on the- 

 other, are sufficiently striking to justify us in regarding them as varieties of one and the same species; 

 while the want of constancy in these peculiarities suggests the inference that these variations are- 

 due to long separation of the races, and to accidental causes, rather than to original diversity of the- 

 stock." The Beaver may thus be regai-ded as a species with two geographical forms (varieties or sul>~ 

 species), viz., Castor fiber, var. europceus, and Castor fiber, var. canadensis. 



So much has been written upon the habits of the Beaver, that the following short statement 

 will suffice to give the leading facts in the natural histoiy of the animal, the accounts of the marvel- 

 lous sagacity of which, given by the older writers, have, perhaps, invested it with an exaggerated 

 interest. 



In populous countries the Beaver is contented, like the Otter, with a long burrow for his 

 residence ; but in the wilder regions of Siberia and North America his dwelling-place is a much more 

 complicated affair. But even in these regions, according to some authorities, a cei-tain number of 

 Beavers ahvays males show a lazy unwillingness to take part in the common labours of the colony; 

 and these, as idlers, are expelled from the community, often with rather severe treatment, and then 

 take up their abode by themselves in holes, which they dig out in the banks of rivers, whence they 

 are called " terriers." On the other hand, it would appear that the bxiilding instinct which is so 

 remarkably manifested by the Beaver is not always extinct even in those which inhabit populous 

 countries, for we have a most interesting account from M. Meyerinck of the construction of a lodge, 

 and even of a dam, by the colony of Beavers on a tributary of the Elbe. 



In North America, from which we have the fullest accounts of the habits of the Beavers, these 

 animals select for their habitation some small stream running through a locality well covered with 

 trees, especially willows, birches, and poplars, upon the bark of which they chiefly feed. These tree* 

 they cut down with their powerful incisor teeth, usually selecting those from the thickness of a man'* 

 arm to that of his thigh, but sometimes even felling trunks eighteen inches in diameter. The* 

 operation, which at first sight would seem to be a rather difficult one for an animal like the Beaver 

 to perform, is effected by gnawing all round the trunk for a certain distance, and gradually working; 

 deeper and deeper into its substance in the middle of the part attacked, until at length the tree stands 



