Floral Abnormality in the Avocado

While observing flower behavior in the avocado, I have been impressed by the frequency of occurrence and variety of abnormalities in the flowers. Aside from the observation of double pistils by Robinson (1) and the report of naked ovules by Bambacioni-Mezzetti (2) there seems to be no mention of such abnormalities. It appears desirable, therefore, to record the results of a study of some 9000 flowers made during 1939-40. The flowers were collected in the University orchard at Los Angeles and in commercial orchards in Los Angeles, San Diego, and Ventura Counties. Included were flowers of commercial varieties of the Mexican and Guatemalan races, the Fuerte variety, and several Mexican seedlings. Before discussing abnormal flowers a brief description of the normal flower is warranted. As shown in Figure 1, the normal flower has a single pistil and nine stamens. The pistil is free from the other floral parts and has a simple, bulbous, smooth ovary and a somewhat elongated style terminated by a slightly enlarged stigma. The stamens are inserted in two whorls. The inner whorl consists of three stamens with staminodes (sterile or abortive stamens) alternating between them. The outer whorl of six stamen