790 NATURAL SCIENCE. dec. 



nearly related to this animal, and then devoting a chapter to its living 

 European congener. The fourth chapter treats of some of the more 

 important of the other larger American Rodents, while the fifth and 

 sixth describe the life-history and geographical distribution of the 

 animal forming the subject of the memoir. These are followed by 

 others treating of the engineering feats accomplished by this interes- 

 ting Rodent, and of the miportance of the animal in commerce and 

 manufacture. In the concluding chapters we have interesting accounts 

 of beaver-hunting, of experiments in the domestication of the animal, 

 ■of its anatomy and osteology, and, lastly, of the beaver in heraldry. 

 Finally, three appendixes reproduce some documents and accounts 

 relating to the animal as known to the earlier settlers. 



Whether, therefore, the reader is interested in the beaver from a 

 purely zoological, from a distributional, from an historical, or from a 

 commercial point of view, he will find plenty of matter in this work 

 worthy of his best attention ; and the book will, indeed, prove abso- 

 lutely invaluable to all who may have to write upon any one of these 

 divisions of the subject. The illustrations with which the work is em- 

 bellished are for the most part excellent, and, as life-like scenes, we may 

 especially call attention to the picture of a beaver-haunt which forms 

 the frontispiece, and to the plate of the " beaver-canal " facing p. 72 ; 

 while as an example of the illustration of a morphological structure, 

 the figure of the tail of the beaver on page 179 is beyond all praise. 



From a literary point of view, Mr. Martin strikes us as being at 

 his best when describing the habits of the beaver in the fifth chapter. 

 In his preface the author takes the precaution to inform his readers 

 that he is not a practised zoologist ; and, this being so, we venture to 

 think he would have been better advised if he had taken counsel from 

 someone who is, in regard to the strictly zoological portions of the 

 work. We find, for instance, on page 35, the following sentence : — 

 " The River-rat, or Coypu as it is called by the natives, is in many 

 ways the intermediate species between the musquash and the beaver, 

 and having been known as the ' Castors of La Plata,' might appro- 

 priately be named the South American beaver." Now, with all due 

 deference to the author, we think that a more inappropriate term could 

 scarcely have been proposed ; and when it is remembered that the 

 beaver, the musquash, and the coypu severally belong not only to 

 three perfectly distinct families, but likewise to as many different and 

 apparently divergent sections of the Rodent order, we quite fail to 

 perceive how the latter can in any sense be regarded as intermediate 

 between the other two. Then, again, we must take exception to the 

 statement on page 36, that the affinities of the capybara, which the 

 author terms the " water-hog," " are evidently there with the 

 pachyderms," — whatever he may mean by the latter obsolete term. 



The author's observations on the habits of the beaver will be 

 found full of interest ; and many erroneous ideas as to the engineering 

 powers of the animal will be, we may hope, thereby finally dispelled. 

 Attention is directed to the prevalent notion that the beaver always 

 fells his timber in the direction of the water ; the true explanation of 

 this being that trees on a river's bank always naturally incline in 

 that direction. The theory that the beaver's "lodge" is merely a 

 special development of the burrow of the musquash is new to us, but 

 is doubtless the true explanation. There are many other observations 

 of equal interest which we must leave the reader to discover for 

 himself in a work which may lay claim to a high position among 

 animal biographies. -n t 



