CHAPTER IX 

 STUDIES OF SPORE-PLANTS 



221. Seeds and Spores. All the plants mentioned in 

 the preceding chapters are characterized by the development 

 of seeds containing embryo plants, and hence such plants 

 are named " seed-plants." But all plants do not produce 

 seeds with embryos ready to unfold when placed in proper 

 conditions for germination. There are a number of types 

 of lower plants without seeds, but which form spores, simple 

 rounded bodies without embryos but able to develop into 

 new plants. Such plants are called " spore-plants. " Ferns, 

 mosses, and mushrooms are examples. It is true that in a 

 seedsman's catalogue we may find " fern seeds " listed ; but 

 this is a careless use of the word " seed/' for what the seeds- 

 man sells are really fern spores. 



However, while spore-plants do not form seeds, seed-plants 

 do have spores. These are of two kinds : (1) the pollen- 

 grains (microspores, little spores), and (2) a mass (megaspore, 

 great spore) inside each ovule from which the embryo 

 (which is at first egg-cell) and endosperm of the seed develop. 

 We see that both seed-plants and spore-plants produce 

 spores. The chief difference is that in all seed-plants the 

 spores develop inside the ovary into embryos (and endosperm, 

 if present in seed) ; while in spore-plants the spores may be 

 scattered far from the plant which produced them and then 

 germinate into new plants. We shall be able to understand 

 this point better after studying briefly the life-history of a 

 fern plant. 



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