The most obvious inheritance is seen in the case of malformations. These represent wide departures from the type of the species as represented in the form. There is no hard and fast line separating the slight departures from the normal type known as variations and mutations, from the malformations. Certain of the malformations known as monstrosities hardly represent the human type. These are the cases in which the foetus is represented in a formless mass of tissue, or there is absence of development of important parts such as the nervous system or there is more or less extensive duplication of the body. There has always been a great deal of popular interest attached to the malformations owing to the part which maternal impressions are supposed to play in their production. In this, some striking impression made on the pregnant woman is supposed to affect in a definite way the structure of the child. The cases, for instance, in which a woman sees an accident involving a wound or a loss of an arm and the child at birth shows a malformation involving the same part. There is no association between maternal impressions and malformations, although there have been many striking coincidences. All malformations arise during the first six weeks of pregnancy known as the embryonic period, in which the development of the form of the child is taking place, and during which time there is little consciousness of pregnancy. Maternal impressions are usually received at a later period, when the form of the child is complete and it is merely growing. It must be remembered also that there is neither nervous nor vascular connection between the child in the uterus and the mother, the child being from the period of conception an independent entity to which the mother gives nutriment merely. Of course, as has been said, the mother may transmit to the child substances which are injurious, and in certain cases parasites may pass from the mother to the foetus. The same types of malformations which occur in man are also seen in birds, and it would require a more vigorous imagination than is usual to believe that a brooding hen could transmit an impression to an egg and that a headless chick could result from witnessing the sacrifice of an associate. The idea of the importance of maternal impressions in influencing the character of the offspring is a very old one, a well-known instance being the sharp practice of Jacob's using peeled wands to influence the color of his cattle. In regard to coincidences the great number of cases in which strong impressions made on the mind of the pregnant mother without result on the offspring are forgotten. The belief has been productive of great anxiety and even unhappiness during a period which is necessarily a trying one, and should be dismissed as being both theoretically impossible and unsupported by fact.