6 2 COMMON LIVER WOR T. 



b. The closely appressed strengthening hairs on the 

 wings ; their origin and direction of growth. 



2. The scales. Notice 



a. The slightly projecting marginal scales, along the 

 under edge of the thallus ; insertion and direc- 

 tion. 



b. The colorless intermediate scales, midway between 

 the edge and the midrib ; insertion and direction. 



Mount both kinds of scales and notice 



c. The shape of each. Draw. 



E. THE CUPULE. Note 



1. Position on the stem. 



2. Shape and size. 



3. The degree of smoothness of the outer and inner sur- 

 faces. 



4. The thin margin, infolded when young ; shape and 

 regularity of the teeth. 



5. The gemma within ; remove some and place on a 

 white surface, and note their form usually two 

 notches can be detected opposite each other. 



6. Draw a cupule with its gemmae. 



F. THE FRUITING BRANCHES. 



1. Position on the stem ; note that they are always con- 

 tinuations of the midrib, and consequently apical, 

 although sometimes, by the prolongation of the wings, 

 appearing to rise from the upper surface. 



2 . The pedicel ; notice 



a. Color and striation. 



