726 MorgarCs American Beaver and Ms Works. [April, 



us descriptions of its characteristics and habitat. Allusion is made to 

 it in the elegies of Ovid, and Juvenal uses some of its supposed idio- 

 syncrasies to give point to his satires. Its ancestry is pre-Adamitic, 

 and can be traced far back into the tertiary period ; fossilized speci- 

 mens of its progenitors have been found side by side with the remains 

 of the mastodon and the raegaceros. It is to the American variety of 

 this cunning rodent that Mr. Morgan's interesting monograph is de- 

 voted. Cuvier, Brandt, and other zoologists have maintained that 

 Castor Earopceus and Castor Americanus belong to entirely distinct 

 species ; but our author, after a very elaborate investigation of the 

 subject, sees no necessity for assigning a separate origin to these va- 

 rieties, although they differ considerably from each other in anatom- 

 ical structure and habits of life. Tiie beaver of the Old World is less 

 sagacious than that of the New ; it does not seem to possess the same 

 social instinct and architectural skill, rarely builds dams or lodges, and 

 never on a large scale, but leads a solitary life in burrows. 



The paradise of beavers on this continent is a district eight miles 

 in length and six in breadth, extending along the southwest shore 

 of Lake Superior, immediately west of Marquette. It is a region 

 of hills and lowlands, covered with dense forests of evergreen and 

 deciduous trees, and well watered by numerous small rivers and 

 lakes, and is therefore especially adapted to encourage beaver oc- 

 cupation and to promote beaver felicity. Within this area, of which 

 Mr. Morgan has made a thorough exploration and gives an excel- 

 lent map, there are sixty-three beaver dams, from fifty to five hun- 

 dred feet in length, and forming ponds which cover from a quarter 

 of an acre to sixty acres of land, besides many others of smaller 

 dimensions. The height of these dams is rarely less than two or 

 more than six feet, although there is one, on a tributary of the 

 Pishikeeme River, which is constructed in a gorge between high 

 hills, and measures twelve feet in vertical height, " with a slope of 

 interlaced poles on its lower face upwards of twenty feet in length." 

 Connected with each of the ponds which have been produced by the 

 dams are usually from two to eight lodges and burrows, -situated either 

 upon the edge of the pond or upon islands within it. The beaver is a 

 strict monogamist, and rears his family in the lodge, retiring into the 

 donjon-keep of bis burrow only in cases of extreme peril. These 

 very curious works are minutely described by our author, and illus- 

 trated by a series of engravings made from photographs. Mr. Moi-gan 

 also gives the most satisfactory account that we have ever seen of the 

 canals which the beaver excavates for the purpose of transporting to 

 its habitation the winter supplies of " wood-cuttings " on which it sub- 



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