Heterozygotes with Dl^6B are lethal at 29^oC, imaginal discs display severe defects. The temperature sensitive period is between 25 and 2 hours before puparium formation, reduction in viability at this period is associated with developmental arrest at the pupal molt. Arrested pupae lack pigmentation, have everted eyes, antennal imaginal discs, everted legs that are inflated and wings appear as bloated sacs. Humeral macrochaetaes are deleted at high temperatures but the temperature sensitive period cannot be determined. Heat pulses immediately after pupariation causes multiplication of thoracic microchaetae, the temperature sensitive period for deletion of microchaetae overlaps and extends later in development. Scarring, eye roughening, disruption of the ommatidial array, eye glossiness and multiplication of interommatidial bristles result from heat pulses an hour after puparium formation. Defects in leg development are more severe with increasing heat pulses during the third instar. Wing venariondefects are observed with heat pulses during third instar development but a temperature sensitive period could not be determined.

Heterozygotes with Dl^vi1 do not differ from Dl^9K homozygotes.

Weak embryonic neurogenic phenotype.

weak allele