The comparative teratogenic potencies of 7,8-dihydroretinoic acid, 7,8-dehydroretinoic acid, 9,10-dihydroretinoic acid, 9-cis-retinal, hydroxenin, oxenin, the C15 analog of all-trans-retinoic acid, abscissic acid, beta-C14 aldehyde, beta-ionone, and psuedoionone were determined in golden Syrian