NO. 2 EXTINCT HORSE FROM ALASKA HAY 15 



Mr. Quackenbush kindly informs the writer that a trader gave him 

 a fossil horse tooth, which had been picked up on the ocean side of 

 an island at the mouth of Schismareoff Inlet. Mr. Quackenbush 

 regarded it as possible that the tooth had been carried there by floating 

 ice ; consequently, the locality is not recognized on the map. 



At the American Museum of Natural History, New York, the 

 writer saw three fragmentary horse teeth, which had been brought 

 back by the Stefansson and Anderson Expedition and found about 

 fifteen or twenty miles southwest of Point Barrow. Since, however, 

 these teeth were discovered on the sites of Eskimo villages, it is prob- 

 able that they had been taken there by human agency. For this 

 reason this locality is not placed on the map. 



One who studies the animals, living and extinct, of Alaska, is 

 naturally led to consider those found on the other side of Bering 

 Strait. The writer has not had the time and opportunity to enter 

 into this subject thoroughly. He has, however, examined the descrip- 

 tions and figures of fossil horses which were prepared by Tscherski 

 (Mem. Acad., St. Petersburg, ser. 7, Vol. 40, pp. 257-380, pis. 5, 6). 

 This author had in his possession a skull, well preserved and lacking 

 few important parts, which had been obtained on Liakhof Island, 

 situated in the Arctic Ocean, latitude 73° north, longitude 140 east. 

 This is more than a degree farther north than Point Barrow, Alaska. 

 The horse to which the skull belonged was supposed to be eight or 

 nine years old. Tscherski figured this skull in three positions and 

 presented a view of the grinding surfaces of the upper premolars 

 and molars. He likewise described the skull in great detail and gave 

 numerous measurements of its parts and of the corresponding parts 

 of many other horses, existing and fossil. The skull had a basilar 

 length of 502 mm., only 4 mm. more than the Alaska skull. It is, 

 therefore, easy to make comparisons between the two. The width 

 at the rear of the orbits is 216 mm., slightly less than in the Alaska 

 skull ; the cephalic index is, therefore, 43 instead of 44.2 mm. This 

 difference is due to the fact that in the Liakhof Island horse the 

 hinder part of the rim of the orbits does not project beyond the 

 zygomatic arches, as it does in the Alaska skull. Tscherski attached 

 considerable importance to this feature ; but a study of the skulls of 

 a number of Grant's zebras seems to show that in this respect, as in 

 so many others, there is a good deal of variation. The f acio-cephalic 

 index in the Liakhof skull is 73.1 ; in the Alaska horse, 73.9. 

 Tscherski measured carefully the postorbital bar, the height of the 

 zygomatic arch below the orbit and behind it, and obtained indices 

 thereof and compared them with those obtained from other horses ; 



