EXTINCT BISONS OF NORTH AMERICA— HAY. 



189 



From the above comparative measurements it will be seen that in 

 some of its dimensions the axis of B. hison is larger than that of 

 B. alleni. At the same time the atlas of the same individual of 

 B. hison has a width of only about 220 mm. A peculiar feature of 

 this axis of B. alleni is that the foramina for the vertebral arteries 

 are wanting. In the next vertebra behind, the canal on the left side 

 has its normal size, while that on the right side is greatly reduced in 

 size. Beyond the differences in proportions indicated in the meas- 

 urements there are few distinguishing features which appear likely 

 to be constant. It is noted that the centrum at the constriction in 

 front of the transverse processes is relatively wider in B. alleni than 

 in B. hison. 



The third, fourth, and fifth cervicals. — These are present and in 

 almost perfect condition. The extremities of the neural spines of the 

 fourth and fifth are broken off. The following measurements are 



furnished : 



Measurements of cervicals. 



Dimensions taken. 



Length of centmm on floor of spinal canal 



Width of anterior articular ball 



Height of anterior articular ball 



Width of hinder articular cup 



Height of hinder articiilar cup 



Distance from hj'popophysis to top of neural spine 



W idth across anterior zygapophyses 



Width across posterior zygapophyses 



From outside to outside of transverse processes 



From outside to outside of anterior extremities of inferior transverse proc 



45 



63 



55 



65 



185 ± 

 108 

 104 

 173 



120 



mm, 



64 



42 



63 



55 



65 



192± 

 114 

 112 

 163 



144 



In the United States National Museum are two horn-cores (Cat. 

 No. 5318), the right and the left, which the writer identifies as those 

 of B. alleni. These were collected in 1905, near Minidoka, Idaho, 

 about 50 miles nearly east of Shoshone, by F. C. Horn, engmeer in 

 the United States Reclamation Service. They were reported by G. 

 K. Gilbert to have been found beneath a flow of basalt. From the 

 same collector and from the same locality there were sent some bones 

 belonging to a large elephant, probably Elephas columhi, possibly 

 E. imperator, a part of a lower jaw of an extinct horse, and some jaws 

 and teeth and some other bones of what appears to have been 

 Camelops Icansanus. All of these bones give evidences of having 

 been buried in a bed of gravel and sand, which adhere closely to them. 



This discovery is an important one, inasmuch as it adds another 

 to the very few instances in which undoubted remains of any bison 

 have been found m this country associated with those of the camel, 

 thus apparently establishing the presence of one or more species at 



