The leaves on cotton plants are simple, but they vary greatly from species to species. Some are almost completely smooth, while others are hairy (with many trichomes). Most leaf blades are thin and papery, but there are some that are thick and leathery. Most species have five lobes, although the actual shape may range from round to deeply cut. On the underside there are three to five main veins. A small, shallow, cup-shaped nectary can be located on the mid-part of the largest vein.
Large leaves are found in alternate order and are arranged along the stem in a spiral pattern. The "phyllotaxy," or common arrangement, is three-eighths of a turn around the stem between successive leaves. In other words, from one leaf to the next directly above it, there are eight leaves, and the spiral passes around the stem three times.
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