Fig. 4. Rescue of lethality at the third larval instar of p89Da-GAL4 x UAS-TNTa progeny by preventing burrowing. Early third instar larvae were placed either in vials or on a thin disc of food and the number that successfully formed puparia were counted. The data represent the percentage survival (mean ± s.e.m.) of four trials each using 100–300 animals. The asterisk represents a significant (Student's t-test, P<0.05) reduction in survival between progeny from UAS-TNTa flies (filled bars) compared with UAS-TNTi (open bars) when raised in vials, whereas no significant difference in survival was seen when larvae were raised on thin food discs. The majority of the dead animals found in the vials were late third instar larvae found deep in the food.