486 Expedition to the 



and willow trees. These trees, as well as all those along the 

 Platte, are low, with very large and branching tops, as is the 

 case with all trees which grow remote from each other. 



In the afternoon hunters were sent forward, but it was not 

 without some difficulty that a single bison was killed, those 

 animals having become much less frequent.* 



* A small fox was killed, which appears to be the animal mentioned 

 by Lewis and Clark, iu the account of their travels, under the name of 

 the burrowing fox, (Vol. 2. p. 351.) It is very much to be regretted, that 

 although two or three specimens of it were killed by our party, whilst 

 we were within about two hundred miles of the Mountains, yet from the 

 dominion of peculiar circumstances, we were unable to preserve a single 

 entire skin; and as the description of the animal taken on the spot was 

 lost, we shall endeavour to make the species known to naturalists, 

 with the aid only of a head and a small portion of the neck of one indi- 

 vidual, and a cranium of another, which are now before us. 



In magnitude the animal is hardly more than half the size of the Ameri- 

 can red fox, (Canis Virginianus, of the recent authors,) to which it has a 

 considerable resemblance. But, that it is an adult, and not the young 

 of that species, the presence of the large carniverous tooth, and the two 

 posterior molar teeth of the lower jaw, on each side, sufficiently attest; 

 these teeth, as well as all the others, being very much worn down, prove 

 that the milk teeth have been long since shed. 



The teeth, in form, correspond, to considerable exactness, with those 

 of our red fox, but the anterior three and four false molares of both these 

 species are sufficiently distinguished from the corresponding teeth of the 

 gray, or tricoloured fox (C. cinereo-argenteus) by being wider at base, 

 and less elongated perpendicularly, and by having the posterior basal lobe 

 of each, longer and much more distinctly armed with a tubercle at tip. 



Besides this disparity of dentition in the red and gray foxes, the gene- 

 ral form of the cranium, and its particular detailed characters, as a less 

 elevated occipital, and temporal crest, more profoundly sinuous junction 

 of the malar with the maxillary bone, the absence of elevated lines bound- 

 ing the space between the insertions of the lateral muscles, passing in a 

 slightly reclivate direction between the orbital processes and the anterior 

 tip of the occipital crest, and in particular the want of an angular process 

 of the lower jaw beneath the spinous process in the cranium of the red 

 fox, ^re sufficiently obvious characters to indicate even by this portion of 

 the osseous structure alone, its specific distinctness from the gray fox. In 

 these differences the osteology of the burrowing fox equally participates, 

 and although besides these characters in common with the red fox, we 

 may observe a correspondence in many other respects, yet there are also 

 many distinctions which the cranium of this small species will present, 

 when more critically compared with that w ell known animal, which une- 

 quivocally forbid us from admitting their identity. The common elevated 

 space on the parietal bones between the insertions of the lateral muscles 

 is one fourth wider, and extends further backward, so as to embrace a 

 notable portion of the anterior angle of the sagitto-occipital crest; the re- 

 cipient cavity in the inferior jaw for the attachment of the masseter mus- 

 cle is more profound, and the coronoid process, less elevated than the top 



