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Developmental patterns of the secondary and tertiary floral organs of Rose of Sharon (Hibiscus syriacus L.) were studied using flowers of nineteen proliferous cultivars. It was found that the first, second, third, and fourth whorls of proliferous flowers were, respectively, sepals, petals, staminal column(changed into male-free axes with tiny petaloids attached), and petaloid-carpels, which were all the primary floral organs. However, the male-free axes of the third whorl of some cultivars developed into accessory flowers which formed abnormal sepaloids, petals, petaloid stamens, and carpels. The secondary floral organs were developed as whorls of several organ primodia within the primary petaloid-carpel whorl. Floral meristem within the fourth whorl (petaloidcarpel) reiterated the ontogeny of petaloid carpels or petaloids, or the developmental program of the three or four outer whorls depending on cultivars. This process of reiterative development continued indeterminately, which resulted in the production of tertiary organ whorls in the same way of the ontogeny of the secondary floral organs. The positions of internal whorls of organ primodia were regular in a cultivar. Some comments are made on a reversion in the order of reiterative organogenesis.
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