82 GENERAL BIOLOGY. 



vessels have disappeared, leaving an irreg- 

 ular space. 

 6. The thin-walled phloem on the side opposite 



the vessels. 



The prosenchyma forming the outer part of 

 the bundle does not belong to the bundle 

 itself. It is a bundle-sheath of modified 

 fundamental tissue. 



HOOT. 



Lay in water on a slide the root of a young mus- 

 tard-seedling grown in sawdust. Cover and ex 

 amine with AA 2. 



1. Find the region in which root-hairs are 



present. 

 Sketch. 



2. Moisten a piece of blue litmus-paper and 



touch it to the root of a fresh specimen. 

 Record the result. 



3. Examine the root-cap of Pontederia or of 



Lemna. 

 Sketch under AA 2. 



BUD. 



Winter buds of elder or of horse-chestnut. 



I. Sketch the ~bud. 



II. Take off the bud-scales and the undeveloped leaves 



in regular order ', beginning with the outermost. 

 Notice the way in which they overlap. 



