182 GLOSSARY 



plants, the members of which have embryos with only one seed- 

 leaf. 

 Nitrification (Latin, nitrum, nitre ; facto, I make). Applied to the 



bacteriological process in the soil by which various organic 



substances containing nitrogen are changed into nitrates. 



The bacteria bringing about the change are called nitrifying 



bacteria. 

 Node (Latin, nodus, a knot or joint). The joints on a stem, at 



which the leaves are generally attached. 

 Nodules (Latin, nodulus, a little knot). Small, rounded swellings ; 



for instance, those on the roots of leguminous plants. 

 Nut (Latin, nux^ a nut, a fruit with a hard shell). Usually applied 



to hard fruits, which do not split open, and contain only one 



seed. 

 Organic (Greek, organon, an instrument or implement). Belonging 



to life. The name given to all substances which, although not 



alive themselves, are the results of living processes. For in- 

 stance, wood, starch, hair, bones, etc. 

 Organism Any living thing, whether animal or plant. 

 Ovary (Latin, ovum, an egg). That portion of the pistil of a plant 



which contains the ovules. 



Ovule (Latin, ovulum, a little egg). The young seeds. 

 Parasite (Latin, parasitus, a fellow-boarder, a guest). An organism 



which lives on and obtains its nourishment from another the 



host. Distinguished from epiphytes which live on but do not 



obtain nourishment from another organism. 

 Petal (Greek, petalon, a flower leaf). One of the leafy bodies, 



commonly brightly coloured, which usually form the showy 



portion of a flower. 

 Pistil (L2&\T\,pistillum, a pestle). The ovary and stigma (which may 



or may not be stalked) of a flower. In some plants the pistil is 



pestle-shaped, hence the term pistil. 

 Plastic (Greek, plastos, moulded). Capable of being moulded or 



worked into various shapes. For instance, potters' clay is 



plastic. 

 Plumule (Latin, plumula, a little feather). The name given to the 



undeveloped shoot (that is, the stem bud) of the embryo. Its 



appearance in such seeds as the bean probably suggested the 



name. 

 Pod A dry (not fleshy) fruit, containing several seeds. A pod 



usually splits open when ripe along both sides. 

 Pollen (Latin, pollen^ anything as fine as dust j hence, very fine 



