LABOIlATOUr STUDIES OF BUDS 25 



Exercise IX. The Nujiueu ami 1'osition of the Buds 



The position of buds in general, wiUi lelerence to the leaves of tlje 

 previous season, must have already attracted attelition. What is that 

 position? AV'hen two or more buds occur together they have, rela- 

 tively to one another, one of two chai-actei'istic arrangements, as seen 

 iu the following species. 



Red Maple. — How nuiny buds in a group? Which ones maybe 

 termed extra, or accessory ? 



Draw enough of the twig to show the essential relations of the buds, 

 both to the leaf scar and to one anothei'. 



Pipevine. — Examine the neighborhood of the leaf scar with the 

 lens. Cut a longitudinal section of the stem through the middle of 

 the scar. Examine the cut surfaces of the bark. Growing points, 

 distinguished by superior greenness, can be made out. Note their 

 number and relative position. 



Make a drawing (enlarged) to show the disposition of accessory 

 buds here found. 



Exercise X. The Wintering of the Young Shoot 



Refer to the records and drawings made in the laboratorj' for the 

 materials of a comparative account of Ijuds, with reference to their 

 adaptations to winter conditions. Protection against sudden chilling 

 is sometimes perfect; in other cases temperature seems to be disre- 

 garded. Arrange the various modes of meeting the dangers of cold 

 in an orderly manner in your account. 



Are there any other sources of destruction besides low temperature? 

 If so, what? And are buds protected against these dangers? 



Exercise XI. The Development or Unfolding of Buds ^ 



The Lilac, forced to grow indoors, may be studied. Determine 

 what parts have grown since the bud came out o£ the typical winter 

 state. Have all grown equally? Have some not grown? 



Draw enough to show what happens to the diffei'ent members of 

 the winter bud. 



If possible, compare with the Lilac the unfolding buds of two other 

 species, as the Buttonwood and the Sycamore iMaple. 



Exercise XII. The XoxnE^ELopjiExr of Buds 



Select a branch of the Horse-chestnut five yeai'S old, or thereabouts. 

 Count the total number of leaf scars. Of these, how many now sub- 

 tend buds, or have subtended l>uds? In how many cases have buds 

 developed into branches or flower clusters? 



I This may be a home experiment. 



