GROSS ANATOMY OF THE ANGIOSPERMS. 301 



§ 4. The Bud. 



Position. — With respect to position upon a twig, buds are 

 terminal or lateral ; and from the fact that the latter grow conspic- 

 uously in the axils of leaves (i.e., in the upper angle formed by the 

 leaf with the twig) they are also known as axillary bads. Strictly 

 speaking, every bud is terminal, for the so-called lateral buds are in 

 reality terminal upon very short lateral branches of the twig. 



Form — In form most buds are ovate ; that is, egg-shaped. They 

 are commonly blunt at the apex, but may be tapering. 



Less commonly buds are spherical, or nearly so, and occasionally 

 they are cylindrical. 



If a cross-section be made of a bud, it is usually rounded ; but 

 it may be compressed (i.e., flattened parallel to its axis) or angular 

 (triangular, quadrangular, etc.). 



Slze^ — Measure the length from base to apex, and the diameter 

 through the thickest part. 



12 3 



Fig. 195.— Scaly buds of various kinds. At 3 are shown buds clustered 

 in axils of the leaves. 



Surface — With respect to their surfaces, buds are for the most 

 part termed scaly, and this term is used especially when the scales 

 are large or somewhat separated from one another. 



Many buds are covered externally with a more or less dense coat 

 of hairs {hairy buds) or down (downy buds). 



Some buds are smooth, the scales themselves having a smooth 

 surface, and the latter being arranged into an even surface. 



For protection against too great loss of moisture from within, and 

 perhaps too great access of moisture from without, many buds are 

 covered with a thin coat of varnish (varnished buds), or they may be 

 waxy, or even glutinous (i.e., somewhat sticky). 



