Page:On a Nearly Complete Skull of Symbos cavifrons Leidy from Michigan.pdf/2

2 search for more of the remains. Nothing further was found.

The skull is evidently that of a large bull of Symbos cavifrons. It tallies so perfectly with descriptions already given that no repetition is necessary. The strong rugosities meeting over the forehead and the lack of any burr at the base of the horns, and the outline of the basisphenoid bone and the relative width of the base of the skull, together with the large size render it certain that the specimen can not be placed in the genus Boötherium.

Some years ago an imperfect skull of a smaller animal referred to Boötherium sargenti was discovered near Grand Rapids and described by Gidley and Hay, but so far as known this is the only specimen referable to Symbos cavifrons yet discovered in Michigan.

Differences of opinion have resulted in considerable discussion of the exact nomenclature of this animal, some considering Symbos as a mature form of Boötherium, but the differences in the two forms as revealed by recovered specimens warrants the retention of the two names, at least provisionally.

Symbos ranged well over the United States in Pleistocene times, one specimen having been found as far south and west as Oklahoma. Allen records eleven known specimens previously collected.

An interesting peculiarity of this specimen is the presence of a large cavity in the left cheek just below and anterior to the orbit. Evidently the animal had suffered a severe injury in some combat from which it had, in part at least, recovered, as the edges of the wound are rounded and partly replaced by new bone.