28 a to the dimensions characteristic of elephants, with the loss of the lower incisors (or with temporary retention of rudimentary ones), while at the same time a true elephant-like trunk must have been developed by the shortening of the lower lip and the prolongation of the combined upper lip and nose.
Specialized species like Mastodon americanus have completely lost the rudimentary premolars.
It is beyond dispute, however, that the game, at any rate in a rudimentary form, was played in the 13th century.
In others, as the thylacine, it is rudimentary, being shed or absorbed before any of the other teeth have cut the gum, and therefore functionless.
In which no such deciduous tooth, even in a rudimentary state, has been discovered.