24 LABORATORY STUDIES OF BUDS 



Horse-chestnut. — Note the arrangement of the scales. Of the leaf 

 scars on the twig. 



Remove the scales by cutting at the base. Separate the wool- 

 covered members within and remove them, counting and noting down 

 the number of pairs. Holding one of these parts by its stalk, scrape 

 off much of the wool, first from the back, then from between the leaf- 

 lets. 



Cut longitudinally down through the bud core, or axis, after remov- 

 ing all scales and leaves. With the lens notice the short, narrow, 

 conical part upon which the leaves proper, not the scales, were inserted. 

 How many internodes ^ in this bud axis ? (Refer to the number of 

 pairs of leaves removed.) How manj^ internodes in the last season's 

 growth on the same twig? Does the bud contain an ordinary year's 

 growth, as to number of internodes and leaves? 



Draw: The bud entire (x 2). One of the young leaves, spread 

 out (x 3). 



Witch-hazel. 2 — Xote the surface of the bud leaves. Scrape. Use 

 the lens. Beneath the exterior coating is the leaf soft, green, and 

 apparently alive, or leathery and dead? Pull the bud to pieces. Are 

 any parts different from the outer leaves ? The latter, as well as the 

 inner ones, finally develop into foliage leaves. There are no scales. 

 Such buds are termed naked buds. Draw the bud entire ( x 2). 



Exercise YHI. 



The Tulip Tree (^Liriodendron). — Xote the flattish form of the bud ; 

 the nearly round scar near the base. Separate the two exterior scales 

 at the tip, and pull them off. Relatively to the little leaf now seen, 

 in what position does the next pair of scales stand? Examine all re- 

 maining parts. AYliat is the round scar at the base of the outer pair 

 of scales ? What is the morphology of the scales ? 



Draw the bud after removal of the outer envelop. 



Magnolia. — Does the caplike covering of the bud consist of two 

 parts fused in growth, or is it single? What is the small scar at one 

 side of the bud? P^xamine the contents of the bud. What is the 

 morphology of the bud cap? Draw the bud, showing the scar. 



Additional Studies 



Make a stud}^ of several other buds as directed by the teacher. 

 Among these, the buds of Mountain Ash (Pyrus Americana or P. 

 Aucuparia), Green Brier (Smilax rotund if alia), Mullein, Dandelion, and 

 some subterranean bud like those of Smilacina, Trillium, Sanguinaria, 

 or Uvularia, are suggested. 



1 Interspaces between leaves. ^ j'or alternative material, see Appendix. 



