Variably abnormal. Severe developmental defects. Partially lethal (approx. 2/3 fail to survive). Adult hermaphrodites have variably enlarged and shortened tails and the body cuticle is twisted. Severe egg-laying defect; some animals have a protruding vulva. Tab. Unc. Lack AVM, PVM, and PLM. ALM often fail to migrate or migrate a shorter distance.