RELATED FORMS 



373 



FIELD TRIP T( I GREENH< >i BE OF w« K)D8 TO 8T1 DY 



FERNS 



Note the color of the plants, the characteristic fern leaf with it .-, >t ii><» 

 or central stalk, its pinnsB or leaflets, and also the method of unrolling 

 from the base to the tip. Note the fruiting dots (sori | on the l «:i«k of tin- 

 leaves. In what kind of soil are ferns found? l>" they gro^ best In the 

 sun or in the shade? l><> the leaves remain green during the winu 

 Note the underground stem and its rums. Look for bads and young 

 leaves. Note the forked veins. 



LABORATORY STUDY 



Examine the cross section of a stem and note the different kind 

 tissue. Draw and label: (1) epidermal tissue on the outside; 2 me- 

 chanical, dark brown tissue in masses near the center; '■'>) conductive 

 tissue, large Openings ; (4) fundamental 

 tissue filling the rest of the space. With a 

 microscope examine the epidermis on the 

 under side of the leaf, noting the shape of 

 the cells and the stomata. Pull off a bit of 

 the epidermis and try to distinguish the 

 green guard cells. Examine a sorus with 

 low power of the 

 microscope and see 

 how it is made up of 

 sporangia on stalks. 



263. Related 

 Forms. — Clul> 

 mosses, horse- 

 tails, and selag- 

 inella (se-laj-in- 

 el/la) are plants 

 which belong to 



the fern group. Clul> mosses bear their spores in a spike 

 on scales which are modified leaves. In appearance these 

 plants are more like mosses than ferns < Figures 102 and 

 403). 



Horsetail, or equisetum, -rows in waste or 'lamp pla< 



Figure 402. 



b, Sporangium ; 



c, Spores. 



Figure 403. — a. Club 

 Moss. 



