Buds and Methods of Branching . 1 1 



more effectively by the dense mass of rust-colored hairs forming 

 a coat beneath the above mentioned corky-tissue. 



The arrangement of leaves on the stem is according to the two- 

 fifths plan. The plan is usually disguised by the twisting of the 

 stem. 



Sketch a branch \, also a vertical section of a bud showing the 

 parts mentioned f . 



In general, branches arise from buds in the axils of leaves. 

 Consequently all branching conforms to the one-half, one-third, 

 two-fifths, or three-eighths, (etc.) plans. In the opposite arrange- 

 ment as in the Horsechestnut, there would be two branches at 

 every node ; in the two-fifths plan there would be just five col- 

 umns of branches around the stem. It is needless to say that 

 such regularitj'^ is seldom seen in nature. 



Variation from the typical methotjs of branching is brought 

 about in several ways among which may be mentioned : — 



1. Non-development of buds. 



2. Non-elongation of internodes. 



3. Twisting of the stem. 



Study and sketch the peculiarities of tlie following buds : 

 Cucumber Tree. (Magnolia acuminata). 

 Hickory. (Carya alba). 

 Lilac. (Syringa vulgaris). 



Balm of Gilead. (Populus balsamifera var. candicans). 

 Beech. (Fagus ferruginea). 

 Hobblebush. (Viburnum lantanoidea). 

 Sumach. (Rhus typhina). 

 Tartarian Honeysuckle. (I^onicera tartarica). 

 Butternut. (Juglans cinerea). 

 Red Maple. (Acer rubrum). 

 Bryophyllum I^eaf. (Bryophyllum calycinum). 

 Willow. (Salix alba var. vitellina). 

 Striped Maple. (Acer Pennsylvanicum). 



Read— Qra.y "Lessons," pp. 27-32, 38-41, 67-71. 



References— Or ay "Structural Botany," pp. 40-56, 1 10-140. 

 Bessey "Botany," pp. 140-144. 

 Bastin "College Botany," pp. 8-18, 182-193. 



