and which in consequence grew crooked, had sons with the same finger on the same hand similarly crooked. The eminent physiologist Dr. Brown-Séquard mentions, that many young guinea-pigs inherited an epileptic tendency from parents which had been subjected to an operation at his hands resulting in the artificial production of fits; while a large number of guinea-pigs bred from animals which had not been operated on were not thus affected. At any rate, it cannot but be admitted that injuries and mutilations which cause disease, are occasionally inherited. But many cases of deformities existing at birth, as hare-lip, are not due to inheritance, although present in the father. They arise from a change effected in the child while in the womb, through an impression made upon the mind of the mother, as will be shown hereafter. LATE MANIFESTATIONS OF THE EFFECTS OF INHERITANCE. Not only are diseases inherited which make their appearance at birth, but those which defer their exhibition until a certain period of life corresponding with that at which they showed themselves in the parents. Thus in the Lambert family, before referred to, the porcupine excrescence on the skin began to grow in the father and sons at the same age, namely, about nine weeks after birth. In an extraordinary hairy family, which has been described, children were produced during three generations with hairy ears: in the father, the hair began to grow over his body at six years old; in his daughter somewhat earlier, namely, at one year; and in both generations the milk teeth appeared late in life, the permanent teeth being deficient. Greyness of hair at an unusually early age has been transmitted in some families. So, also, has the premature appearance of baldness. HOW TO AVOID THE TENDENCY OF INHERITANCE. These facts suggest the practical consideration, that in those diseases the predisposition to which alone is inherited, and which break out only after a lapse of time, it is often altogether possible to prevent the predisposition being developed into positive disease. Thus, for instance, the inherited tendency to _consumption_ remains asleep in the system until about the age of puberty, or later. Therefore, by the use of a diet in which animal food forms a large portion, properly regulated, and systematic exercise in the open air, the practice of the long inhalations before recommended, warm, comfortable clothing, together with a residence, if practicable, during the changeable and inclement seasons of the year, in an equable climate, we can often entirely arrest the development of the disease. Prevention here is not only better than cure, but often all that is possible. Those in whom the disease has become active, must too often, like those who entered Dante's infernal regions, 'abandon hope.' Let our words of caution therefore be heeded.