During the cutting of the second teeth, we observe them come out in the same order as those with which they correspond are detached. 1st. The eight incisors. 2d. The four canine appear. 3d. In the place of the first molar, two new ones are cut; these afterwards have the name of small molars. 4th. The second molar remains, as we have just said; it is the first of the great ones. 5th. At eight or nine years of age, two other molars appear in each jaw. 6th. Finally, at eighteen, twenty, or thirty years, and sometimes later, a third molar is cut; this is called the dens sapientiæ. There is then in each jaw sixteen teeth, of which four are incisors, two canine, two small molars, and three large ones. Sometimes the second teeth while they are forming, instead of appropriating to themselves the nutritive substance of the roots of the first and their partition, leave them untouched; neither are destroyed; and the second teeth are cut at the side of the first which remain in their places. When this phenomenon happens, it is usually only to a single tooth; sometimes, however, it happens to many and even all, and then there is a double row. In general, the second teeth have a tendency to go out at the side of the gums. When very obliquely placed, by a defect of conformation, their crown leans forward or backward; instead of piercing the jaw, they remain always buried in the sockets. _Phenomena subsequent to the Cutting of the Second Teeth._ After being cut, the teeth evidently grow, 1st, in length; 2d, in thickness. It is only the root that is enlarged in the first direction; the crown preserves always the same dimensions; and if in old people it appears longer, it is only because the gums have retracted; a phenomenon which besides we very often observe in persons who have become thin, in those who have made use of mercury, &c. The growth in the second direction is not made without, but only within; the canal of the root and the cavity of the body are constantly contracting, and are finally obliterated. Then the tooth receiving no longer the blood or the influence of the nerves, dies and falls out. But this death appears also to be hastened by the accumulation of osseous substance, of a very great quantity of the phosphate of lime, which predominates there so much over the gelatine, that the principle of life is entirely destroyed, so that in this respect, the shedding of the teeth exhibits a phenomenon analogous to that of the shedding of the horns of the herbivorous animals, of the calcareous shell of the crustaceous ones, &c.