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It is a little shrub, belonging to the Cornaceae, and has broad elliptical undivided leaves. On the middle of the midvein these leaves are seen to bear small clusters of flowers; indeed this is the only place where flowers are produced. Each cluster has from 13-15 flowers, of which some are staminate and borne on stalks, while others are pistillate and nearly sessile.
A variety is called interruptum and another appendiculatum, and these names both relate to the interruption of the leaves by a naked midvein. The leaves are seen to be built up of three parts. The lower half retains the aspect of a limb; it is crowned by a vein without lateral nerves or blade-like expansions, and this stalk in its turn bears a short limb on its summit.
Here the margin of the leaves is deeply cut and divided by many incisions, which sometimes change only the outer parts of the blade, but in other cases may go farther and reach, or nearly reach, the midvein, and change the simple leaf into a seemingly compound structure.
Numerous curious contrivances in these structures to catch ants and other insects have been described, but as they have no relation to our present discussion, we shall abstain from dealing with them. Likewise we must refrain from a consideration of the physiologic qualities of the tendril, and confine our attention to the combination of a limb, a naked midvein and an ascidium.
Those of the Croton, according to our knowledge regarding similar cases, must have arisen at once, and hence the conclusion that the ascidia of Nepenthes are also originally due to a sudden mutation. Interrupted leaves, with an ascidium on a naked prolongation of the midvein, are by no means limited to the Croton varieties.
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