MARCHANTIA POLYMORPHA 85 



small areas into which it is marked off are areolae. 

 In the center of each areola find evidence of a 

 stoma. Is there a midrib? 



5. The cup-shaped structures on the dorsal surface 

 are called cupules. Do they occur on definite 

 portions of the thallus (i.e., margin, midrib, etc.), 

 or irregularly? Describe their color, shape, height, 

 diameter, margin. Are they sessile or stalked? 



6. The non-sexual (vegetative) reproductive bodies 

 within the cupules are brood-buds, or gemmae 

 (sing., gemma). Describe the color, shape and 

 size of one (use hand lens). How are they attached 

 to the plant? Do all the cupules contain them? 

 Explain your observation on this point. 



7. Examine the ventral surface of the plant. De- 

 scribe its color and surface markings, and compare in 

 these respects with the dorsal surface. 



8. Note the root-like filaments or rhizoids. Describe 

 their shape, color, dimensions, and distribution 

 over the ventral surface. 



9. Find purple, leaf-like structures (scales) among the 

 rhizoids, and describe their form, position, and 

 distribution. 



10. Make careful drawings, showing: 



(a) The plant-body, natural size. 



(b) The surface markings of the dorsal surface, 

 enlarged ten times. 



(c) A cupule, side view in perspective, enlarged 

 ten times. 



(d) An outline of a gemma enlarged ten times. 



11. Make a diagram of an imaginary cross-section of 

 the plant-body, passing through one or more cupules 

 (ten times natural size). Label all parts of the 

 drawings. 



