320 



HORTICULTURE FOR SCHOOLS 



Pea, 110 



germination of, 40 

 Peach, diseases of, 185 



history of, 184 



in North America, 184 



insect enemies of, 185 



roots for, 184 



rosette, 258 



-tree borer, 185 



yellows, illustrated, 257 

 Pear-blight, 183, 249-251 



geographical distribution of, 183 



history of, 182 



-leaf rust-mite, 243 



soils adapted to, 183 

 Pears grafted on quinces, 70 



pollination in relation to, 183 



resistant to pear blight, 251 

 Peas, color of according to Mendel's 

 law, 9 



cultivation of, 110 

 Pecan, 193 

 Peppers, 112 

 Periwinkle, 307 

 Persimmon, a semi-tropical fruit, 



204 



Petal, illustrated, 158 

 Petiole of leaf, 30 

 Phenomenal berry, 212 

 Philadelphus, 304 



coronarius, 305 

 Phloem, illustrated, 24 

 Phosphorus as fertilizer, 131-132 



properties of, 131 

 Photosynthesis and respiration, 33 



defined and illustrated, 32 

 Phylloxera of grape, 220 

 Picking of blackberries, 211 



of fruits, 264 

 Pickles, olive, 202 

 Picric acid, a by-product, 290 

 Pistache, 194 

 Pistil, illustrated, 158 

 Pistillate flowers, 160 

 Pith, illustrated, 24 

 Plan, landscape-gardening, 298 

 Plans for garden, 90 



Plant-breeding a science, 10, 11 



-cell, origin of term, 16 



diseases, 246 



improvement, purposes of, 13 



-lice, 225, 238 



materials, 301, 309 



pathology, a science, 246 

 Planting, 50 



-board, 126 



of grapes, 217 



of trees, exercise, 140 



vegetables, 87 

 Plasmolysis, definition of, 18 



exercise to illustrate, 37 

 Plastids, description and illustra- 

 tions of, 20 



Plowing for vegetables, 87 

 Plum curculio, illustrated, 235 



gouger, illustrated, 236 

 Plums, history of, 186 



geographical distribution of, 187 



Japanese, 186 



North American species, 187 



pollination of, 189 

 Plumule, illustrated and described, 

 40, 41 



of corn, 43 

 Poison oak, 305 

 Pollen, collection of, 170 



of potato not viable in North 

 America, 6 



storage of, 171 



transportation of, 164 



-tube, 40 



viability of, 162, 169 

 Pollen-grains, artificial germination 

 of, exercise, 178 



germination of, artificial, 168 



germination of, illustrated, 167 



illustrated, 162-163 



study of, exercise, 178 



where produced, 159 

 Pollination and fertilization, 158 



artificial, described, 170 



definition of, 159 



of almond, 192 



of blackberry, 211 



