And conclusionschapter 27. medical versus mathematical statistics: sex ratio, life duration; summary; chapter 28. models and parameters: general remarks; summary; chapter 29. models and parameters: frustrated hopes in pharmacology; summary and conclusion; chapter 30. models and parameters: diphtheria and scarlatina; summary and conclusions; chapter 31. medical and mathematical epidemiology: evaluation of the malaria situation; conclusions; chapter 32. medical and mathematical epidemiology: short-term predictions: measles; summary.