48 ELEMENTARY BIOLOGY. [VI. 



a. The nodal, internodal, and cortical cells. 



ft. The wall (sac), protoplasmic layer (primordial 

 utricle), nucleus, and vacuole of each cell. (The 

 nucleus, is not always to be found in old cells.) 

 Draw. 



4. Examine sections from the fresh stem to make out 

 the points detailed in B. a. 3. ft. The protoplasm and 

 nucleus are difficult to see. Note the chlorophyll- 

 granules. (See B. b. 7.) 



5, Stain sections of the fresh stem with iodine, and 

 magenta: note the results. 



b. The leaves. 



Examine fresh and chromic-acid specimens. 

 a. The large uncovered terminal cell. 



ft. Then a series of internodal cells, separated 

 from one another and covered in by nodal cells : 

 the sac, protoplasm, nucleus, and vacuole of 

 each. 



7. The chlorophyll: collected into oval granules, 

 and arranged so as to leave an oblique 

 uncoloured band round each cell; the position 

 of these granules in the more superficial 

 layer of the protoplasm. 



8. The protoplasmic movements (see C. a.). 



c. The terminal bud. 



Dissect out chromic- acid specimens as far as pos- 

 sible with needles, and then press gently out in 

 glycerine. Note in different specimens 



