Ermine Cowles Case, On a Nearly Complete Skull of Symbos cavifrons Leidy from Michigan (1915)
“ 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. ”
Ermine Cowles Case, On a Nearly Complete Skull of Symbos cavifrons Leidy from Michigan (1915)
“ The skull is evidently that of a large bull of Symbos cavifrons. It tallies so perfectly with descriptions already given [1] 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. ”
