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come before those of the upper; they commonly appear about
the fourteenth or sixteenth month, and are soon met by those
of the upper jaw. After these, the cuspidati come through,
first in the lower jaw, and then in the upper. At some time
between two years and two years and a half, the second mo-
lares make their appearance, and thus complete the temporary
set of teeth,"
In general, the first dentition commences about the sixth or
seventh month. There is, however, great uncertainty in this
respect. Instances are not wanting, where infants have been
born with two or more teeth, whilst in many others, they have
not made their appearance until as late as one two and even
three years.*
* SPORTS OF NATURE.
Supernumerary Teeth. It occasionally happens that a temporary
tooth, after having given off the rudiment for the permanent one destinjd
to succeed it, gives off a second process which produces a supernumera-
ry tooth. These abortive productions are generally very irregular in
their formations and give the mouth a disgusting and unsightly appear-
ance. They are generally the production of the incisores of the upper
jaw, though they occur in other parts of the mouth.
Of a third set of teeth. " We sometimes though rarely,'' says
John Mason Good, " meet with playful attempts on the part of nature to
reproduce teeth at a very late period of life, and after the perma-
nent teeth have been lost by accident or natural decay.
"This most commonly takes place between the sixty-third and the
eighty-first year, or the interval which fills up the two grand climacteric
years of the Greek physiologists; at which period the constitution ap-
pears occasionally to make an effort to repair other defects than lost
teeth, on which we shall have occasion to treat more at large, when de-
scribing that variety of decay, which in the present system is denomi-
nated climacteric.
" For the most part, the teeth, in this case, shoot forth irregularly, few
in number, and without proper fangs, and even, where -fangs are pro-
duced, without a renewal of sockets. Hence they are often loose, and
frequently more injurious than useful, by interfering with the uniform
line of the indurated and callous gums, which, for many years perhaps,
had been employed as a substitute for the teeth. A case of this kind is
related by Dr. Bisset of Knayton, in which the patient, a female in her
ntnty-eighth year, cut twelve molar teeth, mostly in the lower jaw, four
of which were thrown out soon afterwards, while the rest, at the time of
examination, were found more or less loose.
" In one instance, though never more than one, Mr. Hunter witnessed
the reproduction of a complete set in both jaws, apparent ly with a^ re-
newal of their sockets. ' From which circumstances,' says he, 'and