4 ART. G.— S. YOSHIWAKA AND J. IWASAKI. 



edn'e (jf the nasal loraiiicn it mea.sures 7"", and Iroiii llic p(jstc;i'i(jr eclge 

 of tlie satne foramen to the anterior part of the orl)it '20'"". The nasal 

 foramen is larn-e, oval-shaped, lo'"" lonu' and (i'"' Avide, and ])]aeed 

 (juite in the anterior j)art of the skull (see PI. I). '[\\v width ol" 1 he 

 skull running' throuuh the middle of the rjasal loranien is only lo'", 

 and the distanee hetween the inner sides of the molars of the upper 

 jaAY is 11*"". Tlie lieight of the skull is mon; than IG"" at the 

 posterior end, but aiiteriorly from the point of the insertion of 

 the molar teeth, it thins out (piite rapidly. The molars are 

 found immediately beneath the orbital foramen as shown in V\. 

 ri. Towards the na,sal foramen the jaw becomes more and mr)re 

 flattened, and is ordy 5"'" high at the posterior edge (^f the foramen, 

 whence it thins out towards the anterior extremity. When viewed 

 from above, the nasal foramen is completely surrounded by the 

 premaxillœ, and the nasal bones do n<3t extend to the foramen but 

 lie beneath the premaxillœ. ^laxillœ are well preserved, joined 

 to other bones by distinct sutures. The ui)per surfoce of the upper 

 jaAV is almost smooth and its anterior portion shows no trace of a 

 downward eiu-vature. 



The lower jaw is very low and also does not curve downward. Its 

 ramus is 11'"' liigh and 4.5''" wide at the part where the molai-s grow, 

 but the height gradually diminishes towards the antei-ior part, tinally 

 thinning out at the extremity. The posterior end of the line of 

 junction of the two rami is placed far back, being separated only 

 about 5"" in a direct distance from the root of the molar. The 

 distance from a point between PM., and M to the anterior extremity 

 of the ramus measures about -lO""' in the up])er jaw, but only about 

 3()''"' in the lower. This shows that the u])per jaw protruded over 

 the loAver. 



