1. A detailed account of the losses through death, emigration, &c., will shortly be published as part of a comprehensive report on the health, growth, and environment of the pre-school child. For an account of the sample and methods of the inquiry see Douglas (1951).
2. These temporary absences were due to illness or to removal of a family which was still untraced at the time of the survey.
3. Х2 = 18.767 n = 1 P < 0.001.
4. Comparing the prevalence of regular bedwetting among boys and girls : At 4¼ years χ2 = 3.800 n = 1 0.1>P>0.05. At 7 3/4 years χ2 = 7.622 n = 1 P<0.01.
5. Comparing the prevalence of occasional bedwetting among boys and girls : At 41/4 years ?2 = 13.000 n = 1 P<0.001. At 7 3/4 years ?2 = 2.239 n = 1 0.2>P>0.1.