36 MANUAL OF BOTANY 



distribution and appearance of branches arises fi-om the multi- 

 plication of buds in the axils of leaves. Instead of one bud, 

 we have in rare cases two, three, or more, thus situated {figs. 

 47-49); such are called accessory buds. These buds may be 

 either placed one above another, or side by side. In certain 

 WiUows, Poplars, and Maples, we have three buds placed side 

 by side {fig. 47, a), which frequently give rise to a correspond- 

 ing number of branches. In some Aristolochias, in Walnuts 

 {fig. 48, b), in the Tartarian Honeysuckle {fig. 49, b), and 

 other plants, the accessory buds are arranged one above another. 

 Sometimes the uppermost bud alone develops {fig. 48, 6), as 

 in the Walnut, and thus the branch which is formed arises 

 above the axil of the leaf, and is said to be extra-axillary. In 

 the Tartarian Honeysuckle {fi^ji. 49, b), the axillary or lowest 

 bud is that which forms the strongest branch, over. which a 

 number of smaller branches are placed arising from the develop- 

 ment of the accessory buds. In some trees, as the Larch and 

 Ash, and frequently in herbaceous plants, these accessory buds, 

 instead of forming separate branches, become more or less united, 

 and the branches thus produced then assume a more or less 

 flattened or thickened appearance. Such abnormal branches 

 are commonly called fasciated. Fasciated branches may, how- 

 ever, be produced by a single bud developing in an irregular 

 manner. In some cases, as in Cuscuia, where several buds 

 occur in the axil of the same leaf, this is caused by the branching 

 of the original single one. 



Besides the above three principal cases of abnormal or 

 irregular development of the branches, some minor ones are 

 also met with which arise from the formation of extra-axillary 

 branches in other ways than those just alluded to. Thus the 

 branch may adhere for a short distance either to the stem or to 

 the leaf-stalk, causing curious apparent displacements. 



Sometimes the subtending leaf is suppressed, as in many 

 inflorescences, where the flower seems to spring from the stem 

 quite independently. In some Mosses the normal position of 

 the branch is at the back of the leaf instead of in its axil ; in 

 others it arises at the side of the leaf. These variations follow 

 the mode of division of the cell from which both leaf and branch 

 originate. In some of the higher plants, both in the Vascular 

 Cryptogams and the Flowering Plants, each branch appears by 

 the side of a leaf. In others there is no relation at all between 

 the origin of the two members, as in Lycopodium. Floral and 

 scaly leaves, moreover, do not bear branches in their axils. 



