States and municipalities often demand much more than this; as, for instance, that the medical man shall fill out the whole certificate, including age, nativity, nativity of parents, etc., and that he shall furnish the information to the registrar. In some cases it is provided that any physician having attended a person during his last illness shall furnish the certificate: this would apply to cases where the physician may not have seen the case for weeks before death. While it is most convenient to have the certificate of cause of death upon the same form which contains the data necessary to identify the individual, the certificate should be distinct from the latter, and the duty of making the return to the registrar should devolve on the householder or undertaker, and not on the physician. On the other hand, it is easy for the physician to be hypercritical in these matters: his certificate is to be considered rather as a statement of opinion than as a statement of facts within his personal knowledge, precisely as he would certify as to his own age and birthplace. The compulsory notification of infectious diseases to the health authorities is a matter presenting much greater difficulties than that of certificates as to causes of death. The state has no right to require such notification from the physician without giving some quid pro quo, and it is not expedient to make it compulsory, even with payment, except from physicians employed by the state or municipality, to furnish gratuitous medical attendance to the poor. The state has the right to require such information from the parent or householder, and it has also the right to require the physician to notify the parent or householder as soon as he recognizes the existence of such infectious disease. It is extremely desirable that the health authorities of a city should receive promptly, and direct from physicians, notification of the occurrence of such diseases, and there will usually be no difficulty in obtaining this if the health officer has tact and discretion and the city is prepared to do its duty. This duty is not confined to registering the information or placarding the house, nor will it be properly performed by merely removing the sick person to a hospital and disinfecting the premises. If the case occur in a family which can secure its proper isolation, and the attending physician certifies that it is so isolated and makes himself responsible for its management (for which responsibility he should be paid by the patient or his friends), the health officer should not interfere nor do more than furnish a competent person to secure disinfection if required. The employment of a trained nurse known by the health authorities to be competent and reliable would do away with most of the difficulties connected with such cases in the upper and middle classes of society; and such nurses should be registered just as physicians and midwives are.