Cydadeae, Richard and R. Brown.
Characters.—Gymnosperms with a simple continuous stem, parallel-veined pinnate leaves, and scales of the cone antheriferous.
Properties.—Mucilage and starch are the useful products of this order. They are found in the stems and seeds (see Cycas and Zamia). The seeds of Dion edule yield a starch which is used in Mexico as arrow-root. (Lindley.)