Spontaneous;larval skin extremely translucent, mortality high especially in pupa, female sterile, male fertile but need aid to copulate; activity of Xanthine dehydrogenase trace, excrete xanthine and hypoxanthine but not uric acid: ogt (og of Tanaka, formerly referred to as ot)and ogk og of Katakura) similar but both sexes infertile. See also oq.