INDEX 



229 



Seeds, longevity, 210 

 odor, 209 

 outline, 209 

 reserve food, 207 

 seedling, 211 

 size, 209 

 surface, 209 

 taste, 209 

 testa, 206 

 uses, 210 

 viability, 210 

 Selaginella, 96 



Fig. 54, p. 95 

 Self-pollination, 188 

 Senega, root, Fig. 73, p. 128 

 Sensitive fern, Fig. 38, p. 74 

 Sepals, 109, 177 

 Septa, 112 

 Septicidal capsule, 205 



Fig. 132, p. 205 

 Septifragal capsule, 205 



Fig. 132, p. 205 

 Serrate margin of leaves, 157 



Fig. 93, p. 157 

 Serrulate margin of leaves, 157 



Fig. 93, p. 157 

 Sessile bud, 149 



Fig. 85, p. 147 

 leaves, 154 



Fig. 91, p. 154 

 Shagbark hickory, Fig. 102, p. 



167 



Sheep sorrel, Fig. 92, p. 155 

 Shin-leaf, Fig. 101, p. 166 

 Simple accessory fruits, 197 

 fission, 40 

 fruits, 193 

 rhizomes, 137 

 roots, 130 

 Sinuate margin of leaves, 156 



Fig. 93, p. 157 

 Slippery elm, Figs. 92, 93, pp. 155, 



157 



Smartweed, Fig. 96, p. 161 

 Smilax, Figs. 78, 81, 89, pp. 137, 



141, 152 



medica, root, Fig. 73, p. 128 

 rotundifolia, Figs. 78, 81, 89, pp. 



137, 141, 152 



Smooth bark, Fig. 83, p. 143 

 surface of roots, 132 

 of stems, 143 



Fig. 83, p. 143 

 Smuts, 53 



Solanum tuberosum, Fig. 109, p. 



179 , 



Solid bulbs, 137, 138 

 Solitary roots, 130 

 Solomon's seal, false, Fig. 75, p. 134 



two-leaved, Fig. 98, p. 163 

 Sorbus americana, Fig. 97, p. 162 

 Sori, 78 

 Sorosis, 198 



Fig. 128, p. 200 

 Spadix, 173 



Fig. 106, p. 173 

 Spatulate outline of leaves, 162 



Fig. 96, p. 161 

 Sperm cells, 117 

 Sperms, 63, 81 

 Spicebush, Fig. 92, p. 155 

 Spike, 173 



Fig. 108, p. 173 

 Spinose margin of leaves, 157 



Fig. 93, p. 157 

 Spiny surface of stems, 143 

 Spiraea tomentosa, Fig. 107, p. 174 

 Spirilla, 36 

 Spirogyra, 30 

 Split surface of roots, 131 



Fig. 73, p. 128 

 Sporangia, 48, 78, 101 

 Spore, 40, 49 



cases, 101 



formation, 40 



germination, 68, 80 



mother cells, 101, 116 

 Spore-bearing leaves, 78 



tissue, 67 

 Sporophyte, dicotyledons, 122 



ferns, 72, 82 



horsetails, 86, 92 



liverworts, 60, 62 



monocotyledons, 1 18 



mosses, 71 



white pine, 97, 108 

 Spruce, Fig. 131, p. 203 

 Spurred corolla, 180 

 Squash, Fig. 124, p. 195 

 Staggerbush, Fig. 109, p. 179 

 Staghorn sumac, Fig. 82, p. 142 

 Stalk cell, 102 

 Stalked bud, 149 



Fig. 85, p. 147 

 Stamens, 101, 109, 177, 182 

 Staminate cones, 101 



flowers, 185 

 Steeple bush, Fig. 107, p. 174 



