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60 HUNTER ON THE TEETH.
which respect the Cuspidati are of a middle nature, between
the Incisorcs and Bicuspides, as the last are between the Gus-
pidati and Molarcs ; and thence the Incisores and Molares are
the most unlike in every circumstance.* (c)
* It is here to be understood, that the Teeth from which we take
our description, are such as are just completely formed, and therefore
not in the least worn down by mastication. Our description of each class
is taken from the Lower-Jaw; and the difference between them, and their
corresponding classes in the Upper immediately follows that description.
the typical number of teeth, are the Hog and the Mole. The permanent
teeth in the genus Sus are indicated by the following formula
:
3-3 1-1 4-4 3-3
i c p m =44
3-3 1-1 4-4 3-3
" When the premolars and the molars are below this typical number,
the absent teeth are missing from the fore part of the premolar series
and the back part of the molar series. The most constant teeth are the
fourth premolar and the first true molar ; and these being known by
their order and mode of development, the homologies of the remaining
molars and premolars are determined by counting the molars from before
backwards,— e.g., ' one,' ' two,' ' three,'—and the premolars from behind
forwards—' four,' ' three,' ' two,' ' one.' The incisors are counted from
the median line, commonly the foremost part, of both upper and lower
jaws, outwards and backwards. The first incisor of the right side is the
homotype, transversely, of the contiguous incisor of the left side in the
same jaw, and vertically, of its opposing tooth in the opposite jaw
and so with regard to the canines, premolars, and molars
; just as the
right arm is the homotype of the left arm in its own segment, and also
of the right leg in a succeeding segment. It suffices, therefore, to reckon
and name the teeth of one side of either jaw in a species with the typical
number and kinds of teeth
: e. g., the first, second, and third incisors
;
the -first, second, third, and fourth premolars ; the first, second, and
third molars
; and of one side of both jaws in any case." (1) The fol-
lowing formula therefore represents the homologies of the human teeth
in relation to the typical formula
: i. 1, i. 2 ; c ; p. 3, p. 4 ; m. 1, m. 2,
m. 3;—the third incisor and the first and second premolars being sup-
pressed in Man, as they are also in the Catarhine Quadrumana. (2)]
(c) [The large size of the molars as compared with the incisors,
canines, and premolars, and the regular gradation in size of the human
teeth from the incisors to the molars, are amongst the dental character-
istics which distinguish Man from the higher Apes.]
(1) Owen, op. cit., p. 9.
(2) Owen, Art. Teeth, Todds Cyclopaedia, p. 904.
60 HUNTER ON THE TEETH.
which respect the Cuspidati are of a middle nature, between
the Incisorcs and Bicuspides, as the last are between the Gus-
pidati and Molarcs ; and thence the Incisores and Molares are
the most unlike in every circumstance.* (c)
* It is here to be understood, that the Teeth from which we take
our description, are such as are just completely formed, and therefore
not in the least worn down by mastication. Our description of each class
is taken from the Lower-Jaw; and the difference between them, and their
corresponding classes in the Upper immediately follows that description.
the typical number of teeth, are the Hog and the Mole. The permanent
teeth in the genus Sus are indicated by the following formula
:
3-3 1-1 4-4 3-3
i c p m =44
3-3 1-1 4-4 3-3
" When the premolars and the molars are below this typical number,
the absent teeth are missing from the fore part of the premolar series
and the back part of the molar series. The most constant teeth are the
fourth premolar and the first true molar ; and these being known by
their order and mode of development, the homologies of the remaining
molars and premolars are determined by counting the molars from before
backwards,— e.g., ' one,' ' two,' ' three,'—and the premolars from behind
forwards—' four,' ' three,' ' two,' ' one.' The incisors are counted from
the median line, commonly the foremost part, of both upper and lower
jaws, outwards and backwards. The first incisor of the right side is the
homotype, transversely, of the contiguous incisor of the left side in the
same jaw, and vertically, of its opposing tooth in the opposite jaw
and so with regard to the canines, premolars, and molars
; just as the
right arm is the homotype of the left arm in its own segment, and also
of the right leg in a succeeding segment. It suffices, therefore, to reckon
and name the teeth of one side of either jaw in a species with the typical
number and kinds of teeth
: e. g., the first, second, and third incisors
;
the -first, second, third, and fourth premolars ; the first, second, and
third molars
; and of one side of both jaws in any case." (1) The fol-
lowing formula therefore represents the homologies of the human teeth
in relation to the typical formula
: i. 1, i. 2 ; c ; p. 3, p. 4 ; m. 1, m. 2,
m. 3;—the third incisor and the first and second premolars being sup-
pressed in Man, as they are also in the Catarhine Quadrumana. (2)]
(c) [The large size of the molars as compared with the incisors,
canines, and premolars, and the regular gradation in size of the human
teeth from the incisors to the molars, are amongst the dental character-
istics which distinguish Man from the higher Apes.]
(1) Owen, op. cit., p. 9.
(2) Owen, Art. Teeth, Todds Cyclopaedia, p. 904.
