Fig. 777.—(1) Spike. (2) Catkin. (3) Spadix. (4) Cone.
In the examination of this kind of inflorescence (indefinite or axillary inflorescence), the first object of remark is the general or primary peduncle, termed rachis, and which bears numerous leaflets called bracteoles or bractlets, from whose axils arise the pedicellate or sessile flowers. The lower bracts often produce no flower-buds in their axils, and form instead a whorl surrounding the heads of flowers on the primary axis, and which is called involucre (as in the sun-flower, for instance).
Fig. 778.—Raceme.
Fig. 779.—Panicle.
Fig. 780.—Corymb.
The different varieties of axillary inflorescence are determined principally by the elongation or depression of the axis, the presence or absence of stalks to the flowers, and the form and nature of the bracts. We distinguish—