Leaf margin serrate

Finally, Pseudoleskeella serpentinensis was found within this clade in all analyses. This species differs from other Pseudoleskeella species in being bigger and having thick-walled cells arranged in more or less firm oblique rows, reminiscent of Neckeraceae. The leaf margin of P. serpentinensis is also remotely but quite prominently serrate, a character never found in other species of Pseudoleskeella, but characteristic of both Neckeraceae and Heterocladium. Thus, the placement of P. serpentinensis in Heterocladium or near it seems more likely than in Pseudoleskeella. 

Leaf margin entire (0) or serrulate to serrate (1). Entire margins occur only in a few taxa of the Ptychomniaceae. 

Buckthorn is a shrubby tree that grows 6-12 ft tall. The leaves (up to 6 cm) are simple, ovate elliptic, with serrate margins. Some of the branches end in short thorns. The flowers have four small petals and grow solitary or in clusters from the leaf axis. They are replaced later by a berry that is green at first, turns red, and then turns black at maturity. The berry contains up to four seeds. This ornamental shrub is often found as hedges throughout the eastern... 

Description Herbaceous perennial. Stems single or multiple, 40-150 cm taU, tomentose. Basal leaves 3-5-lobed cauline leaves with rounded or cordate base and acuminate apex, margins coarsely serrate. Flowers up to 3 cm across, clustered in leaf axils. Epicalyx with 8-12 segments. CoroUa pale-pink with 5 petals. Fruit a disc-shaped schizocarp, with 15-25 small, laterally flattened mericarps. Seeds kidney-shaped. 

With the exception of the first leaf (which may be simple), all leaves are compoimd. In some species the mid-rib is extended slightly to form a mucronate tip. Other features on the leaf may be serrated margins, the presence or absence of marks, colour and hairiness (Fig. 19.12 and Fig. 19.13). The leaves are arranged alternately on the stem, and they consist of a stalk which beats two or more leaflets according to the species (Fig. 19.14). 

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