(二)花外蜜腺是指分布于幼茎或叶(叶片、叶柄和托叶)等营养器官上的蜜腺。叶上的花外蜜腺比较普遍,常见的有:1.位于叶脉上如棉花叶的背面中脉甚至侧脉上有蜜腺;桂樱叶背面的中脉与侧脉所成的内角有蜜腺。2.位于叶缘上,如臭椿、桃、凤仙花等叶片近基部的叶缘上有腺体;油桐、千年桐、蓖麻等叶背面的裂刻处有腺体。 (b) Flower nectaries are nectaries distributed on vegetative organs such as young stems or leaves (leaves, petioles and stipules). The floral nectaries on the leaves are more common. Commonly there are: 1. Located on the veins, such as the midrib of the cotton leaves and even the nectaries on the lateral veins; the internal angles formed by the midrib and the lateral veins on the back of the osmanthus leaves have nectaries. 2. Located on leaf margins, such as skunk, peach, impatiens and other leaves near the base of the leaf margin of glands; tung tree, millennium tung, castor and other leaves on the back of the crack carved at the gland.