No. 1.] TRITUBERCULAR MOLAR. 23 
tebrata. He describes human dentition more thoroughly than previous authors, and 
refers to the tritubercular modification in the following language (p. 444): “The 
superior molars, like those in the lower jaw, are three in number, and have quadritu- 
bercular crowns normally, but many examples can be found in which the postero- 
internal cusp, the last one added in the quadritubercular molar, is little more than a 
cingulum, and is scarcely entitled to the appellation of a cusp.” And in a footnote 
he observes, “It is probable that this condition, of which I have seen a number of 
examples in the higher races, is a degenerate one, and is an effort to return to the 
tritubercular stage.” 
Dr. Wortman has, at my suggestion, examined a large number of Esquimaux crania 
contained in the Army Medical Museum at Washington, which were not accessible 
at the time of my visit to it. He confirms the value of the tritubercular second supe- 
rior true molar as a race character. 
The conclusions described in this paper are mostly embraced in a preliminary one 
which appeared in the American Naturalist for November, 1886, 
NoTre.—The discussion of the functional relation of the tritubercular to the 
quadritubercular molar dentition on a preceding page, has reference to the early 
mammalian types, and to the question of origin of the quadritubercular at that 
period. The relations cf the parts of opposite jaws are different in the trituber- 
cular races of men, since the interaction of the crowns in mastication is no longer 
alternate but opposite. 
