During this period we have in the tissues, instead of a development and renewal of protoplasm, the tendency to an accumulation of fat; and in the whole organism, chiefly in the tissues of the arterial system, we find the tendency to a deposit in their structure of an amorphous substance which converts the supple elastic canals into rigid tubes; and from this a general slowing up of the organic functions (circulation, oxidation, secretion) results; the blood, not reaching the degree of elaboration which it possessed before, acquires a greater acidity, and cannot by the ordinary excretory channels so quickly get rid of the catabolic products with which it is charged. By reason of these conditions the organism of older people undergoes a sort of slow and gradual intoxication, which, at the same time as it shows itself in the individual by the gradual languishing of all his functions, influences in a disastrous manner the germs which develop within him, and predisposes them to become beings condemned to degeneracy. Consequently this cause of degeneracy enters the general category of intoxications. GENETICS AND EUGENICS. (Abstract.) By R. C. Punnett, _Professor of Biology, Cambridge_. To the student of genetics, man, like any other animal, is material for working out the manner in which characters, whether physical or mental, are transmitted from one generation to the next. Viewed in this way he must be regarded as unpromising, not only from the small size of his families, the time consumed in their production, and the long period of immaturity, but also because full experimental control is here out of the question. For these reasons man is of interest to the student of genetics, chiefly in so far as he presents problems in heredity which are rarely to be found in other species, and can only be studied at present in man himself. The aim of the Eugenist, on the other hand, is to control human mating in order to obtain the largest proportion of individuals he considers best fitted to the form of society which he affects. It is evident that to do this effectually he must have precise knowledge of the manner in which transmission of characters occurs, and more especially of those with which he particularly wishes to deal. Precise knowledge is at present available in man for relatively few characters; and those characters, such as eye-colour, and certain somewhat rare deformities, are not the kind on which the Eugenist lays great stress. The one instance of eugenic importance that could be brought under immediate control is that of feeble-mindedness. Speaking generally, the available evidence suggests that it is a case of simple Mendelian inheritance. Occasional exceptions occur, but there is every reason to expect that a policy of strict segregation would rapidly bring about the elimination of this character.