248 APPENDIX 



for the new leaves, to replace the fallen ones, begin? Of what advan- 

 tage would it be to have the new ones ready for unfolding at the first 

 moment of warm spring weather ? If leaf rudiments were formed in 

 the fall, what arrangements would be made for their protection ? A 

 number of different devices for shielding the tender young leaves 01 

 leaf rudiments will probably come to mind. Later, in the laboratory, 

 it will be seen whether in nature these devices have, in effect, been 

 realized. A cursory examination of twigs bearing buds may be made 

 in class at the time of this discussion. 



Exercise VII. Illustration 3. Alternatives are the Hobblebush 

 (Viburnum lantanoides), V. Lantana, V. cotinifolium, V. furcatum, and 

 the Butternut (Juglatu cinerea). 



Exercise IX. Illustration 2. " Dutchman's Pipevine " (Aristolochia 

 Sipho}. 



Exercise X. may be a written exercise to be handed in. 



Exercise XI. The development of buds is a very interesting subject 

 for study. The chief difficulty is to get buds to grow well indoors. 

 Many buds refuse to develop at all in the early winter, but make some 

 growth later in the year. If the subject is taken up in the spring, 

 material may be got from the trees, and cut branches may be forced. 

 A damp atmosphere favors development. In March I have forced 

 Lilac, Rose, and Am. Larch to unfold enough for study, in 8 days; 

 Acer platanoides (Norway Maple) excellent example of scale de- 

 velopment in about 20 days; and Buttonwood (Platanus occiden- 

 talis) in 14 days. The latter gives a good illustration of the stipular 

 nature of some bud scales, as its scales grow. 



Exercise XIII. The White or Silver Maple and the Rock or Sugar 

 Maple, both illustrate the superior development of the horizontal buds 

 and branchlets. The material should be selected for the purpose. 

 Sometimes the vertical shoots will be decidedly the stronger; such 

 examples would be interesting. 



Chapter V. Exercise XIV. The Shepherd's Purse is a common 

 weed, widely distributed, appearing very early in spring in yards and 

 by roadsides. Its root is much better for general morphology than 

 the fleshy roots of vegetables. Dandelion is fairly good. If root hairs 

 do not show well, grow a few seeds of any kind in sand, and call 

 especial attention to their manner of clinging to the sand, even when 

 the plantlet is pulled up. 



Exercise XV. The Trumpet Flower (Tecoma radicans) is best. 

 English Ivy (Hedera Helix) may be used. 



Exercise XVI. Sweet Potato is suggested. Carrot includes short- 

 ened stem. Dahlia will serve. 



Supplementary Subjects. i. Material may probably be obtained 

 from some greenhouse. The function of the roots is commonly mis- 

 understood. Vapor of water is not condensed by them, except as dew. 



