108 



PLANT-LIFE 



purposes of distinction, being called " secidiospores." 

 They are of a yellow colour. But the secidiospores do 

 not infect the Barberry. They can thrive and follow 

 out their purpose only if they are carried by rain or 

 wind to a cereal plant, such as Wheat, or other member 

 of the Grass family. Thus, the teleutospores produced 

 on, say, Wheat give rise to sporidia, which can infect 



only the Barberry, and the 

 secidiospores developed on 

 the Barberry are the means 

 whereby the Fungus re- 

 turns to the Wheat or 

 other member of the same 

 family — surely a most re- 

 markable life-cycle. 



We are sorely tempted 

 to linger with -the Fungi, 

 and make a study of a 

 goodly number of forms; 

 but the space we can spare 

 to this fascinating group of 

 plants is nearly exhausted, 

 so we must pass rapidly to 

 the consideration of the 

 structure and development of a type representing the 

 Basidicmycetes, an Order which includes the more 

 familiar and conspicuous Fungi, such as Mushrooms, 

 Toadstools, Puffballs, etc. About 10,000 species of 

 Basidiomycetes have been distinguished. The Order 

 has its name from the basidia (basidium, a little pedestal), 

 or mother-cells, which bear the spores in the ripe fruits. 

 The Order includes two important Suborders, the 



Fig. 35. — Puccinea gramlnis. 

 x 10. 



Portion of lower surface of leaf of 

 Barberry. The swollen part (P) 

 bears a group of jEcidium-cups (a). 



