A PRELIMINARY STUDY OF THE INFLORESCENCE TYPE ARISING FROM BAMBOOS AND ITS VARIATION

There are two types of the bamboo inflorescences which have been proposed in the present paper. One is the true inflorescence, and the other is referred by some authors to false one. The true type of bamboo inflorescence has a continuous main axis, develops in a semslauctant period of histogenesis, and grows from a determinate portion (or special portions) of the bamboo-body. The fundamental units of this type are genuine spikelets usually each with a distinct pedicel. The so-called false type, however, is surely a blooming leafy branch and not the inflorescence proper. It has a jointed axis (originally a vegetative branch) with spikelets attached to the nodes. It develops in iterauctant periods of histogenesis, and the spikelets (or pseudospikelets) grow indeterminately on the nodes of any branching axis or even of main culm. The fundamental units found in the so-called false type of bamboo inflorescence usually are pseudospikelets. They are generally sessile or nearly so and mostly in compact clusters or fascicles.It is the writer's opinion that mostly the so-called false type may have evolved from the true one. For example, the inflorescence of Thamnocalamus spathiflorus Munro is racemose with 2-3 spikelets, which is very similar to the flowering branchlet of a more primitive bamboo species with "false" inflorescence Indosasa hispida McClure. Of course, between the true type and the so-called false one a reverse direction of evolutionary line can also be found.