INTRODUCTION. 29 



without instruction, no one can say that with each new 

 swarm some bees do not go which are older than those of 

 the same year, and which may act as teachers in the build- 

 ing of a new comb," etc. That bees and ants actually teach 

 each other, and that the younger do other and easier work 

 than the older, and have quite other instincts, will not long 

 remain unknown to the reader of this book. The beavers 

 also, about whose remarkable architectural skill so much 

 truth and so much falsehood have been written, instruct one 

 another ; and if we read in nearly all books on Animal 

 Psychology the well-known stories of the young beavers, 

 repeated and used for the hundredth time, how they are 

 taken from their mothers immediately after birth and 

 brought up artificially, and with materials provided in their 

 cage manufacture a dam after the most approved rules of 

 beaver-dam-construction, then, without making the experi- 

 ment, we may say decisively that the story is false, or at the 

 best much exaggerated. The young beaver, impelled by his 

 inherited tendency to build, may very well make attempts 

 to construct a dam, as, according to P. Flourens (pp. 53 

 and 185), one of the animals brought up by Cuvier 

 actually did ; but that a dam was constructed by it according 

 to all the rules of beaver architecture, without aid or in- 

 struction from its older companions, can be believed all the 

 less, since the beaver-trappers expressly assure us that, 

 according to their observations, young beavers stay no less 

 than three years with their parents in order to be instructed 

 by them. " The young ones," says Schmarda (" Intelli- 

 gence in Animals," p. 207), " live until the third year with 

 their parents, and are then sent to build for themselves." 

 On the other hand, the animal has so much intelligence not 

 ruled by instinct that it can turn its architectural ability to 

 special account according to circumstances. E. Menault 

 (p. 195) relates that a beaver, kept encaged at the Botanical 

 Gardens in Paris, one cold night, when the snow came 

 through the palings of his enclosure, built up his cabbages, 

 fruits, and twigs of trees into an excellent shelter against 

 the annoyance, weaving the tree twigs into the grating, and 

 the snow itself serving for mortar. 



" On all sides," says Espinas, the distinguished author of 

 the " Treatise on Animal Societies," " it is admitted, even by 

 those least favorably disposed to animals, that the latter act 



