The child is born with all its muscles in place, and all fully formed in that every muscle fiber the child will ever have has been produced previous to birth. In fact, as soon as the full equipment of muscle fibers has been laid down the body loses the power to form more, so that if, through injury, one is so unfortunate as to have some of his muscle fibers destroyed he will have to get along for the rest of his life with those that are left. The gaps in the muscle tissue that are produced by injuries are filled up by a kind of connective tissue known as scar tissue. The muscle fibers are all present, but smaller and weaker than they will be later. The connections between muscles and nerves are also pretty well established at the time of birth, so that the body and limbs can be moved freely, even if not at all efficiently. Not only are the motor nerves formed and in connection with the muscles at and even before birth, but the sensory nerves and most of the central nervous system are ready to begin functioning as well. Some reflex actions, including a few that require quite elaborate muscular and nervous coordination, are performed very shortly after birth. One famous example, that has been much cited as tending to reinforce the belief in man’s descent from tree-dwelling ancestors, is the curling of the fingers about a slender rod that is pressed against the palms. In most very tiny babies the grasp thus secured is strong enough so that the child can be raised and held in the air, supported wholly by its own grip. Sneezing, which is really a very complex act, requiring accurate cooperation on the part of many muscles, is done successfully by very young infants. The reflex of sucking, which is of paramount importance, in that without it the child would almost inevitably starve, is present practically from birth. Another important early reflex is that of crying. It is a curious thought that this reflex, by which bodily discomfort is made known, and through which relief may be summoned, is revealed at the very instant of birth, in connection with the drawing of the first breath, while the contrary reflex of laughter, by which bodily well-being is expressed, puts in an appearance only after some weeks or even months.