The centre of the corresponding period of procreation (25th December to 26th March) is in February (carnival). This seems to confirm the suspicion that during the wine harvest and carnival an increased procreation of feeble-minded occurs (procreation during drunkenness?). We cannot suppress the remark that the fluctuations of the curve for the feeble-minded are much too small to admit of the drawing of an ætiological conclusion, but the fluctuations of the intelligence curve and the illegitimate curve partly exceed the limits of probable error. The peaks of both birth curves in February, correspond to a peak in the procreation curve in May. Perhaps one may attribute them to the existence of a remnant of a period of "heat" (or a rutting season) in man. [Sidenote: C 98] +Lead.+ Whereas the +germ cells+ are well protected against many harmful influences from without which affect the soma of the mother, they +and the foetus produced from them suffer considerably from+ some. Amongst their deadliest enemies are +certain poisons+, and +notorious in this respect is lead+. Table C 98 gives two sets of statistics on this point, they justify the law in Germany, and in other States, forbidding female labour to deal with lead and lead-containing materials. Paul's figures, showing that lead poisoning of the father is also extremely adverse to the production of a healthy progeny, are remarkable. [Sidenote: C 99] +Female Labour.+ A baneful influence on reproduction is brought to bear by the growing quantity of professional female labour away from home and by the economic emancipation of women. Evidence of this is given in Table C 99--"+female labour and child mortality+"--the data of which are taken from Prinzing's work. Infant mortality is higher the larger the percentage of females employed in factories during the child-bearing period. This is partly due to interference with breast-feeding and partly to the unfavourable influence on pregnancy. [Sidenote: C 100]