146 Proceedings of the Biological Society of Washington. 



pared with that of californicus and colusus ; palate short and rather 

 broad; postpalatal shelf of moderate breadth, fiat; postpalatal notch 

 moderate; mastoids rather short, directed anteriorly. Lower jaw absent. 

 Teeth gone except left hind molar, which is short, heel small, obliquely 

 truncate on outer side (as in klamathensis) . 



Cranial comparisons. — Similar in general to klamathensis but fronto- 

 nasal region strongly dished, rostrum shorter, broader, flatter on top. and 

 depressed instead of elevated ; zygomata more widely outstanding; palate 

 broader; occipital overhang less. 



Skull measurements (c? old, type). — Basal length 327 mm.; occipito- 

 nasal length 323; palatal length 183; interorbital breadth 84.5. 



Ursus mirabilis sp. nov. 



Type No. 137471 d* adult, U. S. National Museum, Biological Survey 

 Collection. From Admiralty Island, Alaska. Collected June 26, 1905, 

 by Cyrus Catt. 



Characters. — A true Grizzly, of medium size, related to stikeenensis of 

 the mainland, and having the same high bulging forehead; external 

 characters unknown. 



Cranial characters. — Adult male (the type): Skull of medium size, 

 short, with rather broadly spreading zygomata and highly arched (almost 

 domed) frontal region. Frontal shield of moderate breadth, short-pointed 

 posteriorly, rising abruptly from rostrum, convex both anteroposteriorly 

 and transversely, slightly sulcate medially, moderately swollen on each 

 side of sulcus; postorbital processes moderate, broader than peglike, 

 slightly decurved (continuing convexity of frontals) ; fronto-nasal region 

 strongly dished; rostrum high, narrow, strongly sloping; zygomata rather 

 broadly outstanding, slightly bowed ; palate and postpalatal shelf rather 

 broad; underjaw short ; ramus bellied posteriorly; coronoid blade high 

 and rather vertical, the apex not reaching plane of condyle. Upper 

 canines rather long; molars rather broad and short. 



Cranial comparisons. — Ursus mirabilis requires comparison with only a 

 single species — stikeenensis of the neighboring mainland. Compared with 

 stikeenensis: Size smaller; frontal shield narrower and more bulging an- 

 teriorly, rising more abruptly from rostrum ; rostrum narrower, materially 

 higher, and more sloping; zygomata more widely outstanding; occipital 

 overhang more pronounced ; palate and postpalatal shelf similar; lower 

 jaw less massive ; coronoid blade narrower and higher. Teeth similar 

 but heel of last upper molar much shorter. 



Skull measurements ( c? ad. type). — Basal length 308 mm.; occipito- 

 nasal length 310; palatal length 168; zygomatic breadth 230; interorbital 

 breadth 81. 



Ursus nuchek sp. nov. 



Type No. 146459 c? old, U. S. National Museum, Biological Survey 

 Collection. Type from head of Nuchek Bay, Hinchinbrook Island, 

 Prince William Sound, Alaska. Collected Sept. 15, 1905, by C. Swan- 

 son. 



