On the other hand, the ejaculatory duct with its verticillate sac in the male of Cypris and other genera is a feature scarcely less remarkable.
Many of the small female flowers borne on shoots with foliage of the Cupressus type consist of spirally disposed and not verticillate scales, e.g.
These causes of change in phyllotaxis are also well exemplified in the alteration of an opposite or verticillate arrangement to an alternate, and vice versa; thus the effect of interruption of growth, in causing alternate leaves to become opposite and verticillate, can be distinctly shown in Rhododendron ponticum.
Such whorled or verticillate bracts generally remain separate (polyphyllous), but may be united by cohesion (gamophyllous), as in many species of Bupleurum and in Lavatera.
Carpellary leaves, and that in the progress of development these leaves separated from them, leaving the placentas and ovules free in the centre; or by supposing that the placentas are not marginal but axile formations, produced by an elongation of the axis, and the carpels verticillate leaves, united together around the axis.