430 



RECREATION. 



ical characteristics. 1 he teeth marks can 

 easily be detected in the picture of a stick 

 with a cut end. I cut this stick out of a 

 dam. One photo of a beaver's skull shows 

 the sharp incisor teeth and the effects of 

 wear on them. As in the case of all ro- 

 dents, a beaver's incisors are its cutting in- 

 struments, and have a hard enamel outside, 

 backed by a softer dentine which wears 

 away more rapidly than the surface enamel. 



















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AMATEUR PHOTO SY W. H. BERGTOLD. 



BEAVER S LOWER JAW. 



Dotted Line Showing Length to which Incisor Tooth 

 can be Withdrawn. 



In this way the "knife" is always kept 

 sharp. Were the growth of a tooth 

 stopped, or by some fault or accident the 

 natural apposition of lower to upper in- 

 cisor prevented, the unapposed tooth would 

 grow to undue proportions, finally piercing 

 the opposite jaw. These cutting teeth have 

 the growing matrix situated far back in the 

 jaw or skull. This is due to a need of 

 hardening the tooth before its end comes 

 into use, and so the distance from the ma- 

 trix to free edge is great, to allow of crys- 

 tallization, as it were, of the dental sub- 

 stance. The lower jaw is shown with an 

 incisor tooth in situ, the dotted lines on the 



AMATEUR PHOTO BY W. H. BERGTOLD. 



beaver's lower jaw. 



Incisor Tooth Withdrawn to Full Length. 



background indicating the distance and the 

 direction the tooth can be withdrawn before 

 being wholly disengaged, and the interrupt- 

 ed lines on the bone surface outlining ap- 

 proximately the tooth socket. The other 

 photo shows the tooth withdrawn to its 

 full length. What a toothache a beaver 

 might have ! 



The houses 'have been of peculiar inter- 

 est to me. All I have seen have been huge 

 piles of sticks most intricately interwoven, 

 and more or less plastered and piled over 

 with mud. The house in the North fork 

 of Monument creek is a green mound, 

 grasses and weeds having 'taken root on its 

 mud top. I am led to believe, through my 

 talks with Indians in Canada, from my 

 hunting friends, and from personal obser- 

 vation, that the sticks are first piled up, 

 and the dwelling chamber is afterward cut 

 out. As a dam is building the busy work- 

 men probably scorn to take an hour off for 

 lunch, but take a bite as they work. 



The Colorado law protecting beaver is 

 wise. I wish it might be enforced. 



She: Do I talk in my sleep, John? 



He: No. Not when you are asleep, 

 Maria — thank heaven! — Indianapolis Jour- 

 nal. 



" A true poet writes poetry because he 

 can't help it." 



"Oh, no; a true poet writes poetry be- 

 cause nobody can stop him." — Chicago 

 Record. 



