Overexpression of Src64B^KR.hs.2sev by heat shock at 37^oC for 1 hour every other day during development results in reduced viability. Approximately 65% of embryos carrying two copies of Src64B^KR.hs.2sev show abnormalities in the central nervous system when Src64B^KR.hs.2sev is expressed using a 30 minute heat shock at 37^oC between 5 and 8 hours of development. Gaps between some segments are seen within the longitudinal connectives, and there is fusion of the anterior and posterior commissures within some segments. Expression of Src64B^KR.hs.2sev causes mild roughening of the eye. A small number of ommatidia have less than seven rhabdomeres.