wts³³⁸ mutant tracheal cells are overgrown with the most dramatic overgrowth seen in the terminal cells. Although some extra branches observed in these mutant terminal cells may simply be terminal branches that are normally present but bigger than normal (and hence easier to detect), there clearly are also extra branches not present in wild-type, such as those in proximal positions of terminal cells. In many cases, these extra seamless tubes course through the soma of the terminal cell, giving a multiple lumen phenotype.