The published version of Figure 1 on p. 334 was incorrect, the correct version is given below. The caption as originally printed was correct.
Fig. 1. A total of 39 trapped +/+ pregnant dams were sacrificed to obtain their fetuses. The mean t haplotype transmission ration was 49·9% with a standard error of 5·5%. 30 of these 39+/+ dams had fetuses with mosaic t complex genotypes. Following Ben-Shlomo et al. (2007), a mosaic t mouse was classified as t/+.
p. 338 last line of text, correct citation is: (Baker, unpublished data).
