70 Merriam Preliminary Synopsis of American Bears. 



the zygomatic arches are more strongly bowed outward and their pos 

 terior roots stand out at nearly a right angle to the cranial axis ; the 



interpterygoid fossa is 

 longer; the ascending 

 arms of the premaxillee 

 are shorter; the jugal is 

 more extended anteriorly, 

 reaching up in front of the 

 lachrymal foramen [in 

 beringiana it falls consid 

 erably short of this fora 

 men]. The audital bullre 

 differ strongly in young 

 skulls of the two species, 

 though they come to re 

 semble one another more 

 in old age. In the young 

 of the Kadiak animal they 

 are very much heavier, 

 more convex inferiorly, 

 and broader at the outer 

 or meatus end. In the 

 adult female the skull is 

 relatively more elongated than in the male, and the frontal region is less 

 elevated. 



The first upper and last lower molars (particularly the latter) are de 

 cidedly smaller in the Kadiak animal, while the middle lower molar is 

 nearly the same size in both species. The lower carnassial has strong 

 intermediary cusps or tubercles, as in the Grizzlies. 



Measurements of skull of type. Greatest length of cranium (front of pre- 

 maxillary to end of occipital crest), 440; greatest basal length (gnathion 

 to occipital condyles), 392; basal length (gnathion to basion), 377 ; basilar 

 length of Hensel, 370; zygo mat ic breadth, 277 ; occipito-sphenoid length 

 (basion to suture between basi- and presphenoid ), 1 05 ; postpalatal length, 

 107; basion to plane of front of last upper molar, 238 ; interorbital breadth, 

 98; distance between postorbital processes, 132.5; occipito-nasal length, 

 358 ; height of brain case above pterygoid, 160 ; height of brain case above 

 basisphenoid, 123. 



Remarks. Compared with Ursus beringiana* skulls of adult 

 U. middendorffi can be distinguished at a glance by the difference 

 in the breadth of the frontal and the degree of elevation of the 

 supraorbital region. Skulls of any age may be distinguished by 

 the peculiarity of the anterior end of the jugal, which in the 

 Kadiak animal reaches upward to articulate with the lachrymal, 



FIG. 7. - Kadiak Bear. 

 Ursus middendorffi. 



* Ursus arctos var. beringiana Middendorff, Untersuchungen an Schadeln 

 des gemeinen Landbiiren, p. 74, 1851. 



