Skunk-cabbage, 11, 122. Slave-making ant, 112. Slavery, 106. Slaves, 104, 108-112. Smilax, 12, 30, 113, 117. Snakes, 143, 155. Snipe, 22. Snow, 70, 140, 141, 147, 152-156, 160, 161, 166, 181. Snowbird, 27, 66, 190. Snow-buntings, 22, 24. Snowflakes, 8, 22, 133, 153, 165. Snow-storm, 153. Socialism, 96. Social wasp, 86, 89. Solitary wasps, 89. Solitude, 177, 188. Solomon's-seal, 62. Song, 18-20, 31, 32, 41-43, 45-51, 53, 55, 67, 119, 138, 161, 163, 168-170, 178, 190, 198. Song-birds, 189. Song-sparrows, 17, 31, 45, 50. Sorrel, 57. Sou'wester, 206. Spagnum, 68, 122, 168. Sparrows, 16, 17, 31, 37, 38, 42, 43, 45, 46, 50, 70, 118, 155, 162. Spatter-docks, 152. Speedwells, 57. Spicebush, 58, 170. Spider, 29, 51, 65, 78, 83-89, 117. Spider's egg, 160. Spider-web, 64, 84. Spinnerets, 85, 88, 89. Spinning, 84, 88, 93. Spores, 119. Spray, 203, 207. Spring, 11-14, 17, 21, 24, 45, 50, 51, 68, 112, 114, 119, 144, 157, 170. Spring beauty, 1, 20, 61, 169. Spruce, 6, 32, 57, 66, 67, 181, 182, 185, 186. Spur, 174. Spurge, 76. Spurred violets, 169. Squirrels, 42, 120, 121, 125, 139-142, 156, 187. Stag-horn sumac, 123. Stamens, 78. Starfish, 203, 204. Star of Bethlehem, 56. Stars, 128. Stinging ants, 95. St.-John's-wort, 63, 114, 149. Storm, 205, 206. Strand, 85, 89. Strata, 179. Strawberries, 57. Stream, 48-50, 67, 169, 170, 177, 178, 180-182, 187, 195. Stridulating, 54. Stumps, 114. Sugar-maple, 124. Sugar-pine, 185-187, 195. Sumac, 3, 15, 68, 80, 82, 83, 88, 123, 124. Summer, 60, 66, 67, 70, 71, 126, 152, 154, 168, 181, 207. Sunflowers, 59, 122. Sunrise, 194. Sunset, 194, 199. Surf, 7, 203, 207. Swallows, 19, 25, 26. Swamp milkweed, 72. Swamps, 13, 15, 18-20, 31, 40, 45, 47, 68, 73, 113, 114, 123, 125, 126, 134, 168. Swan-song, 163. Swarming, 98. Sweetbrier, 1. Sweet fern, 127. Swift, 22, 30. Sylvan, 49. Tabriz, 126. Tansy, 74. Temperament, 43. Temperate zone, 131. Tendency, 97. Tertiary animals, 131. Thaw, 135, 151, 168. Thicket, 16, 75, 118, 122. Thistle-down, 30, 64. Thistles, 59, 64, 74, 75, 135. Thorax, 86, 95, 102, 105. Thoreau, 177. Thrasher, 49. Thread, 84, 87, 88. Thrushes, 8, 9, 16, 30, 42-46, 48, 51, 62, 190. Thunder-storm, 182. Tide, 204. Tiger, 199. Timber, 181. _Timbre_, 200. Timothy, 64. Toads, 19, 50, 132, 155. Towhee, 182. Track, 148, 156, 161, 162. Trail, 177, 178, 183. Trail-horse, 177. Transmutations, 60. Tree ferns, 117. Tree-sparrows, 70, 155, 162. Tree-swallows, 19, 25. Tree-toads, 50, 52. Trillium, 62. Trough, 203. Trout, 172. Trout-rod, 195. Trunk, 141, 158, 185, 186, 188. Tufted titmouse, 47. Tulip trees, 58. Tupelo, 113, 124, 125, 134. Twilight, 192, 199. Twisted-stalk, 62. Twittering, 19. Undergrowth, 59. Upholsterer-bee, 82. Urchins, 203, 204. Veery, 44. Vespa, 78. Vessel, 206, 207. Vesuvius, 58. Viburnum, 113, 124. Violets, 13, 20, 21, 26, 57, 59, 60, 62, 129, 169. Vireos, 5, 8, 31, 36, 37, 93.