46 CASTOROLOGIA. 



already enriched the hunter. Great changes have taken place since 

 the family left in the spring ; the ice has carried away part of the 

 dam, and the lodges show sad need of repairs. After a careful 

 sur^'ey of the surroundings for signs of danger, the work begins, 

 and the kittens learn to employ more usefully their sharp cutting 

 teeth. The old beavers cut down great trees, which fall with fear- 

 ful crashing, the noise echoing through the quiet woods, and driving 

 the workers into shelter till all danger is passed ; the young ones now 

 set to cutting the smaller branches and swim away with them to the 

 dam, where they are placed to advantage and plastered over with 

 mud, roots and grass ; while stones are added to keep all tight and 

 firm. 



The dam has first to be rebuilt and strengthened, so that the water 

 will rise to the required level to enable the colony' to swim comfor- 

 tably under the ice, and to allow for the storing of a good supply of 

 branches. Then the lodge is repaired ; the old bedding cleaned out, 

 and together with a supply of branches is heaped upon the roof of 

 the lodge and a fresh covering of mud-plaster, the same as used for 

 the dam, is laid over all, and thus the home is prepared for the long, 

 cold winter. The retreats in the banks — the burrows or " washes" 

 — are enlarged or increased in number, and a full supply of branches 

 having been cut and laid in the deep pools near the lodges, all is 

 ready for the coming frosts, which soon put an end to work and lock 

 the beavers completely under the heavy covering of ice. For some 

 time afterwards the beavers swim about under the ice prospecting 

 for food, pulling up the great roots of the water-lilies and dragging 

 them to the burrows, there to enjoy the feast ; but even this occa- 

 sional treat gets monotonous and the confinement has its effect on 

 the beavers, who sleep much longer and do less travelling as the 

 winter advances. 



Towards the spring the food will sometimes become exhausted, 

 and it is then necessary for the old beavers to seek a fresh supply. 

 An outlet through the ice has to be effected, and then follows the 

 very difficult and dangerous undertaking of travelling over the snow 

 and felling some trees ; all the enemies of the beaver are looking with 



