Bin 



V///: DIGESTIVE APPARATUS IN MAMMALIA. 



After their comph-te eruption from the alveolar c ivities, the Dog's teeth arc no 1. 

 d oatWttda. They are remarkable for their brilliant whit- -m :-.-, \\hii-h tin . 

 to tin 1 til'M-mv tit' e. ni> lit en their covering of eimmel. 



Tin- Ciii has thirty teeth : twelve incisors, four tusks, and fourteen nmlmv, eight of 

 whieh are in the upper, and six in the lower jaw. 



All these teeth arc constructed on tlie same type as those of the Dog. The tusks are 

 deeply striated on their external surface, instead of being smooth. 



(The importance of a correct knowledge of the p. -rind of eruption, shedding, repla<-iir_r, 

 and general wear of the teeth of the domesticated animals, as a guide t. 

 induces me to give the table on page 363 (from Leyh), us indieating ut a glance tl 

 tit which the teeth appear, are shed, and replaced in the different ere id 



Baumeister divides the successive evolutions in the wear of the tables ut the II 

 incisor teeth into four periods from six years to extreme old age. The lirst, the tran-- 

 versely-oval period, extends from six to twelve years: the round, from twelve t.. 

 eighteen years; the triangular, from eighteen to twenty-four years, ami the ant.-r. .- 

 posterior oval or triangular, from twenty-four years and upwards. Girard and other 

 French authorities shorten these periods somewhat. The triangular period, for in>tanee, 

 only lasts from fourteen to seventeen years.) 



COMPARISON .OF THE MOUTH OF MAN WITH THAT OF ANIMALS. 



The brevity of Man's face influences the shape of the mouth ; therefore it is pro| or- 

 tionally shorter and wider than in the domesticated mam nals. 



Fig. 168. 



AMI;KII-I-.I>I i;i:ioii SUTIO.N OK Tin: IHMA.S TAOt, 

 a. Septum of no>c, with section of hard palate below it ; '. Tonkin' : .-. Si-ction of 

 Hoft palate; ',</, l.ip-; . Uvula; /. Ant. -rim- ,-irrh. or pillar of fanci-s ; /. \'<* 

 terior ai-i-li ; t, Toii.sil ; />, Pharynx ; //, Hyoid bone ; /.', Tliyroid 



cartilage; , K|ii','l"ttis ; r, (ilnttis; 1, I'n-ti-rior o|n-nin;; of nan-> : 



I'luriuni ; 4, SujM-rior o 



Knstai-lii.-iti t nl.-. 



of laryn I iat" O-SMJ. 



!, Isthmus 

 <;. Orili,:,. 



