20 Zoology of Colorado 



group. The tracing of these migrations, extinctions and sur- 

 vivals is a fascinating pursuit for those who have the necessary 

 imagination and philosophic insight. 



One genus of extinct camel, the Alticamelus or "high-camel," 

 was a most extraordinary creature. It had a long neck almost 

 like that of a giraffe, and must have been able to browse off 

 comparatively tall trees with ease. Members of this genus 

 existed in the region east of the Rocky Mountains during Mio- 

 cene and Pliocene time; remains of two species have been found on 

 Pawnee Creek. There were true camels in North America as 

 late as the Pleistocene. We are, geologically speaking, only a 

 little too late to see camels and mammoths on our plains or in 

 our mountain parks. By a similarly narrow margin we have 

 missed the great ground-sloth, Mylodon. This belongs to the 

 order Edentata, a South American group which invaded North 

 America in Tertiary times. The name, implying the absence of 

 teeth, is quite inappropriate for the ground-sloth, which has 

 large teeth. The armadillo, still living in Texas, belongs to the 

 Edentata. A kind of ground-sloth seems to have been con- 

 temporaneous with man in South America, and pieces of its hairy 

 skin, found in a cave, may be seen in the British Museum. About 

 a mile south of Walsenburg, Mr. E. A. Lidle found a large skull 

 which belonged to some unknown animal. After his death, Mrs. 

 Lidle kindly presented it to the University of Colorado, and we 

 were much interested to see the first actual proof that ground- 

 sloths lived in Colorado. The specimen is remarkable for its 

 great size, the length being somewhat greater than that of any of 

 the many examples obtained from the asphalt beds of the Rancho 

 la Brea near Los Angeles, California. The Walsenburg skull 

 was described and fully illustrated in the University of Colorado 

 Studies, June 1909. 



It can hardly be doubted that man reached America from the 

 Old World. In this matter tradition and zoological evidence 

 appear to agree. Until very recently, it was supposed that the 

 Anthropoid Primates, the group of the gorilla, chimpanzee and 

 orang, never existed on this side of the world. Consequently 

 there was some stir in scientific circles when in 1922 Professor 

 H. F. Osborn announced the discovery of an Anthropoid in the 

 early Pliocene of Nebraska. The animal, called Hcspcropithecus 



