=Sterility.=--Sterility denotes the incapacity for procreation of children; is also applicable to both sexes, but more usually in reference to the female. A person may be impotent without being sterile, although the former is usually regarded as implying the latter. On the other hand, a person may be sterile without being impotent, the former not necessarily denoting the latter. In reference to nullity of marriage, if natural sexual relations are not and cannot be consummated, the marriage will be declared null and void, provided that such inability of consummation was unknown to the person bringing the action for nullity before marriage. Impotence is sufficient ground for bringing an action for nullity, provided it was present at the date of the marriage, that it is irremediable, and that the person bringing the action was not informed of it previously. Should, however, the marriage have been consummated and impotence develop later, there will be no grounds for such an action. =Impotence and Sterility in the Male.=--This may arise from some _organic defect_ of the organs or _functional disorder_. In reference to the former there are certain abnormalities of the male organs which have to be considered. Monorchids, men in whom one testis is absent from the scrotum, are not necessarily impotent or sterile; nor are cryptorchids, where both testes are undescended. In many of these cases spermatozoa are absent from the seminal fluid with consequent sterility; on the other hand, procreation has taken place, proving that cryptorchids are not necessarily sterile. Absence of the penis may be the result of want of development, injury, disease, or operation. The penis may be present but attached in its whole length to the scrotum; this may be remedied by operation. Epispadias, so often associated with ectopion vesicæ, as a rule renders an individual impotent and sterile. On the other hand, hypospadias does not necessarily bar procreation; it will depend largely upon the position of the urethral opening, and the possibility of its being remedied by operation. Removal or destruction of both testes renders a man sterile eventually, but not necessarily impotent. Functional disorder due to disease may give rise to impotence, although the organs may remain anatomically perfect. Diseases such as diabetes and influenza, neurasthenia, tabes dorsalis, myelitis, mumps, and orchitis, and injuries to the head may be causative factors in impotence.