12 ■ THE FLOWER GROWERS GUIDE. 



The case of ferns may serve as au illustration of cryptogamic fertilisation, which 

 is in principle the same, but varies more or less in detail in other cryptogamic plants. 



In the mushroom, propagation is carried on by spores {conidia), which give rise 

 to the silvery cobweb-like mycelium, or real mushroom plant ; that which is of 

 economic interest to us in the shape of the mushroom itself being really the fruiting 

 phase or state only of the fungus. 



What is a Plant? 



When we come to ask ourselves the question, "What is a plant?" tlic answer is 

 not so easy as one might at first suppose. A plant is a 

 very variable quantity ; indeed, it may be a single cell or 

 two the size of sparrowshot, as in Wollfia, a kind of root- 

 less duckweed, or it may be a giant forest tree composed 

 of millions of cells, towering 100 to 200 feet in height, 

 and weighing many tons. 



AYe may say a plant is a living organism, the living 

 principle being protoplasm {pro = earliest ; plasma = stuck 

 together), and its active working principle is a form of 

 protoplasm called chlorophyll (c/^/oyos = green ; p]ijjllon — -A, 

 leaf), 0]- green leaf. 



Few more beautiful objects are revealed by a powerful 

 microscope than the living and moving matter protoplasm, 

 tloatiug the chlorophyll grains through the cells of vallis- 

 ncria in an ever-ceaseless round under appropriate con- 

 ditions of temperature and healthy growth (Fig. 'i). The 

 lesson thus taught is that we must cherish the leaves of 

 our plants, and by goud culture enable them to do their 

 wo -drous work (see pages 19, 20). 



It is very difficult at first sight to distinguish between some plants and the lower 

 animals, such as the zoophytes. Animals, as a rule, however, have only one mouth ; 

 they ingest solid as well as liquid food, and can move about freely, and their digestive 

 work is carried on in one large bag or stomach ; whereas plants ingest their food by 

 thousands of little mouths or pores (called stomata), and they can only take in food 

 in a soluble state, that is to say, either in a liquid or in a gaseous form. 



Then plant food is absorbed by the leaves from the air, food solutions are also 



Fig. 3. Floaving or Stueajiixi.; 

 Peotoilasm in Vallisneeia 

 (Kebneu). 



