Spikelets unisexual, male and female in separate inflorescences or on different parts of the same inflorescence.
Anton Kerner has shown that crowded inflorescences such as those of Compositae and Umbelliferae are especially adapted for geitonogamy.
I, Branch with male (a) and female (b) inflorescences; 2, bract with three male flowers; 3, bract with three female flowers; 4, infrutescence; 5, fruit.
In the conifers proper the female reproductive organs have the form of cones, which may be styled flowers or inflorescences according to different interpretations of their morphology.
The male and female inflorescences have the form of simple or paniculate spikes.
Numerous circular pits occur on the concentric ridges of the depressed and wrinkled crown, marking the position of former inflorescences borne in the leaf-axil at different stages in the growth of the plant.
A third series of inflorescences, termed mixed, may be recognized.
According to the mode and degree of development of the lateral shoots and also of the bracts, various forms of both inflorescences result.
Compound definite inflorescences are by no means common, but in Streptocarpus polyanthus and in several calceolarias we probably have examples.
Tabular View Of Inflorescences A.
The female inflorescences vary considerably in organization; in some species the axis of the spike bears solitary ovules, each accompanied by a few bracts, while in others the lateral appendages are catkins, each containing from two to several ovules.
There is good evidence that many of the seeds belonged to Cordaitales, especially those seeds which had a flattened form, such as Cardiocarpus, Cycadinocarpus, Samaropsis, &c. Seeds of this kind have been found in connexion with the Cordaianthus inflorescences; the winged seeds'of Samaropsis, borne on long pedicels, are attributed by Grand' Eury to the genus Dorycordaites.
Some of the fossils referred to the genus Kaidocarpon, and originally described as monocotyledonous inflorescences, are undoubted Araucarian cones; other cones of the same type have been placed in the genus Cycadeostrobus and referred to Cycads.