288 HORTICULTURIST'S RULE-BOOK. 



Pistillate. Bearing pistils alone ; female. 



Plantlet. The little plant just emerged from the seed. It 



becomes a plant when it is able to assimilate and lead an 



independent existence. 



Pod. A dry seed-vessel which splits open at maturity ; capsule. 

 Pollen. A product of the anthers, which is capable of fertiliz- 

 ing the stigma. It is usually granular and powdery. 

 Pollination. The conveyance of pollen from the anther to the 



stigma. 



Polygamous. Said of plants or species which bear both per- 

 fect and imperfect flowers. 

 Pome. A fleshy fruit with a papery core surrounded by a 



greatly thickened calyx, as the apple, quince, etc. 

 Race. A fixed variety ; that is, a variety which reproduces 



itself more or less uniformly from seeds. 

 Raceme. A more or less elongated and simple flower-cluster 



with one-flowered pedicels. 

 Regermination. Second germination. Seeds which have been 



checked after germination has begun may resume the 



process under favorable conditions. 

 Root. A part of the plant which bears neither leaves nor buds, 



and which absorbs nourishment for the plant, or serves as 



a support for it. It may be subterranean or aerial. 

 Root-cap. The covering upon the end of a growing root. The 



elongation of the root takes place just behind the root-cap. 

 Root-grafting. Grafting upon the root. 

 Root-hair. A very delicate prolongation of a cell of a young 



root. Root-hairs are active agents in absorbing plant-food. 

 Rot. The decay of the thicker part of plants, however brought 



about ; the amount of moisture present determines 



whether it shall be called wet or dry rot. 

 Runner. A procumbent or creeping herbaceous shoot which 



takes root at the joints. 

 Rust. Any plant-disease in which the surface of the plant is 



apparently converted into a powder or scurf, particularly 



when of a ferruginous or blackish color, as wheat-rust. 

 Saddle-graft. A sort of grafting in which the scion is split 



