774 



MAMMALIA. 



warm flesh. Most are bold and fierce animals, with keen 

 senses and quick intelligence, and often much beauty of 

 form and marking. 



FIG. 417. Lower surface of dog's skull. 



O.C., Occipital condyle; B.O., basic-capital ; T., tympanic bulla; 

 wt.c., postglenoid process behind fossa for condyle of mandible ; 

 .S., basisphenoid ; P.S., base of presphenoid ; K., vomer ; 

 M.2, second molar; M.I, first molar; Pm.i-^, premolars, the 

 4th the large carnassial ; ., canine; /.i-3, incisors; Pmx., 

 premaxilla; mx. t maxilla; Pal., palatine; /., jugal ; A.S., 

 alisphenoid ; /*/., pterygoid ; Sg., squamosal (the reference line 

 points to the glenoid fossa). 



Almost all have well-developed claws ; there are never 

 fewer than four toes. The teeth are always rooted, except 

 in the case of the tusks of the walrus; the canines are 



