198 TRILLIUM. 



imens of roots, rootstocks, stems, leaves, flowers 

 and fruit ; potassic hydrate ; magenta ; and iodine. 



LABORATORY WORK. 



GROSS ANATOMY. 



A. GENERAL CHARACTERS. Note 



1. The main axis, consisting of a thickened, horizontal, 

 under-ground stem, the rootstock, and a single vertical 

 branch, the aerial stem, bearing a terminal flower. 



2. The rootstock, bearing as lateral appendages the roots, 

 and modified leaves in the form of broad membranous 

 scales. 



3. The aerial stem, bearing as lateral appendages a whorl 

 of three leaves, and the parts of the flower. 



B. THE ROOTS. Note 



1. Their arrangement on the rootstock. 



2. The almost entire absence of branching. 



3. The surface, especially the transverse wrinkles on older 

 parts. 



4. The root-hairs. 



Mount a transverse section of the proximal portion of a 

 large root, and notice 



5. The presence and relative areas of three regions: 

 a. The cortical region of two layers : 



i. An outer layer of small cells. 

 ii. An inner layer of large, irregular, loose cells, 

 often torn through in sectioning, the unequal 



