154 



BOTANY. 



Synopsis 



Moss plant 



(Polytrichum 



orffther moss). 



Plant body, a small leafy stem, with rhizoids. 



Protonema (branched green threads 



which precede the leafy stem). 

 Male plants with a rosette of leaves at 

 the end. 

 Antheridia. 



Spermatozoids. 



Female plants, leaves closed together at 

 the end. 



Archegonia. 



Archegonium contains egg. 

 f Capsule wall. 



( Fruit capusule. 

 1 Stalk. 



Vegetative part 



of plant. 

 Three forms. 



Fruiting part. 



| Lid. 



Teeth at mouth. 

 i Spores. 



(The hood is not a part of the capsule, but is the remains 

 of the archegonium.) 



Material and apparatus. The pigeon wheat moss (polytrichum) is an ex- 

 cellent one to study, but one should not be confined to this if it is easier to 

 collect other species which show strong differences between male and female 

 plants. Male and female plants, as well as plants with fruit, some of which 

 should possess the "hood," should be preserved dry, or in 2% formalin. 



Free hand, or prepared, sections of the sexual organs. 



Apparatus, the same as in Chapter XXIV. 



