Mesodermal derivatives are disorganized in Ogt expressing embryos. Images of fixed embryos processed for in situ hybridization to reveal expression of ntl at 10 hpf (A-C) or MyoD at 14 hpf (D-F). At 10 hpf, ntl is expressed in the axial mesoderm in controls (A). ntl expression is truncated (B) in class I embryos, and more severely truncated in class II embryos (C). MyoD marks trunk somites on either side of the midline at 14 hpf (D). Some somites are missing in class I embryos, but many of the remaining somites are abnormally wide (E). In class II embryos, somites extend around the circumference of the embryos (F).