65 



fourth premolars; and in advance of tliis several small ones exist. In llie 

 specimen represented in Fig. 11, Plate II, the mental foramen is situated 

 below the first premolar. 



Measurements from several specimens of lower jaws of Hyrachyus agrarius 

 are as follows : 



Leugth of space occupied by the molar teeth 



Distance from incisive alveoli to first premolar 



Length of hiatus between canine and first premolar 



Depth of jaw below last molar 



Depth of jaw below last i>remolar 



Breadth of jaw at caniue alveoli 



Breadth of jaw below hiatus 



Length of symphysis 



LiDes. Liues 



25 

 13 



14 

 12 



28 



42 

 24 

 13 

 IS 

 15 

 13 

 10.J 



Liucs. 



44 



20 

 10 



Measurements of upper molar teeth are as follows: 



luchcs. Lines. 



Length of the entire upper molar series 3 9 



Length of series of premolars • 1 8.1- 



Length of series of molars 2 1 ', 



Diameter 

 Diameter 

 Diameter 

 Diameter 

 Diameter 

 Diameter 

 Diameter 



of first premolar . . , 

 of second premolar 

 of third premolar . . 

 of fourth premolar . 



of first molar 



of second molar . . . 

 of third molar 



Comparative measurements of two upper last premolars are as follows : 



Lines. 



Fore and aft diameter in both 7 



Transverse diameter in one 8^ 



III the other 9 



Measurements of lower molar teeth are as follows : 



Length of the entii'e lower molar series . 



Length of series of premolars. 

 Length of series of molars . . . . 



Lines. 



20 



Lines. 



42 

 19 

 24 



Lines. 



44 

 20 



2U 



9g 



