The Relationship of the rroinaxilhi in Bears. 171 



xillae from the frontals. In all the Genus Ursus, examined by myself, 

 the premaxillae touch the frontals. The Skull in Ursus Malay - 

 anus is short and broad in front, and the parietal region rounded, 

 the length of the Naso - Premaxillary articulation = 26 mm and of 

 the Naso frontal articulation =12 mm. The breadth of the Prema- 

 xilla-frontal articulation = 4 mm. The breadth of the Premaxilla 

 along the alveolar margin 20 mm. 



Ursus Americanus. Naso-Premaxilla . 37 mm 

 Naso-frontal ... 24 mm 

 Breadth of Fronto-Premaxill articulation 4 mm 

 Breadth of Premaxilla at alveolus . . 30 mm 

 Summit of Nasal at the same level as fronto-maxillary articulation. 

 Nasal-Premaxilla ... 45 mm 

 Ursus sp. — Naso-Frontal .... 40 mm 



P. M. Frontal suture 4 mm oblique 



Breadth of P. M. below 30 mm. 



The Fronto-Premaxillary Suture is 11 mm in front of orbit. 

 Ursus Maritimus Med. Naso-Premax. articulation 45 mm 



Naso-Frontal .... 44 mm 



Fronto-P. M. artic. . . 2 — 3 mm 



Breadth below 36 mm 



The Premaxillo frontal articulation is 9 mm in front of the orbit. 

 The summit of nasals is 25 mm above the summit of the maxillo- 

 frontal articulation, whilst in U. Malayensis the summit of nasals is 

 only 2 mm above froiito maxillary suture. In the Ursus sp. already 

 referred to the Nasal tops are 15 mm. above the maxillaries. In 

 a full grown U. Maritimus (Thalassarctos Maritimus) the nasals are 

 4 inches long, and the premaxillae 5 inches. The distance of the 

 lower border of the Nasals from the alveolar Margin is 3^/^ inches, 

 the Naso-premaxillary articulation is 45 mm. 



In Ursus Py rena eus the distance from the alveolar margin of the 

 Premaxilla to the nasal in the middle line is 2'^;g inches. The Naso- 

 premaxillary suture is three inches in length. The Premaxilla is one 

 inch wide below by 3^/^ inches in length. The Nasal 3 and the 

 maxilla 3'^^ inches. The maxilla is thus shut off from the nasals. (D.) 



