Mammals 25 



a generic sense, true Machaerodus belonging to the Old World. 

 The specimens may be seen in the Colorado Museum at Denver. 



Another very interesting extinct carnivore is Ursavus pawn- 

 iensis, discovered by Childs Frick in the mid-Miocene beds near 

 Pawnee Buttes. The generic name Ursavus implies an ancestral 

 bear, but as Frick has recently (1926) shown in admirable detail, 

 the animal belongs to an extinct group (Hemicyoninae) and is not 

 a bear. 



The dog family (Canidae) is represented in Colorado by 

 three genera, Urocyon (the word literally meaning tailed dog), 

 Vulpes and Canis. The gray fox is Urocyon cinereoargenteus 

 scotti of Mearns, a cumbersome name indicating that our animal 

 belongs to the subspecies described from Arizona, and not to the 

 eastern representative of the genus. The gray foxes, with their 

 large bushy tails, are beautiful animals, and run into a number 

 of distinct species or races. There are no less than four forms 

 peculiar to as many islands off the coast of California. The true 

 foxes, Vulpes, include with us the western red fox Vulpes ma- 

 crourus of Baird, and the swift fox, Vulpes velox of Say. The 

 former, much the larger of the two, is found high in the mountains; 

 the latter occurs on the plains. The swift fox was one of the many 

 discoveries of Long's expedition, and another was the gray wolf, 

 Canis nubilus of Say. The type locality of the latter is in Ne- 

 braska, but Warren states that wolves appear to be found all over 

 Colorado, though they seem to be more abundant in Wyoming. 



The coyotes also belong to Canis, but are placed with the 

 jackals in a subgenus Thos. Warren cites five kinds of coyotes 

 as reported from Colorado, but their separation is made with 

 difficulty. Formerly these animals were referred to a single 

 species, Canis latrans of Say, first found in Nebraska during 

 Long's expedition. In 1897 Dr. C. H. Merriam wrote a paper 

 in which he named supposedly new coyotes from Nebraska, 

 Nevada, Utah, Arizona, Lower California and Mexico. This 

 led to much controversy, and a debate was arranged in Wash- 

 ington between Merriam and Theodore Roosevelt, the latter 

 maintaining in a friendly spirit that the subdivision was needless. 

 One who was present stated that the feeling of the meeting 

 seemed to be with Roosevelt, yet there is no doubt that 

 the critical studies of Merriman have been of great value. 



