Robin, American (_Merula migratoria_), 72; courtship of, 78, 79; duels of, 78, 79, 142, 190; singing a brown thrasher's song, 267; mobbing a blue jay, 289, 290; a brood of young fed by a wren, 314, 315; notes of, 57, 159, 163, 166, 167, 267; nest of, 15, 91, 124, 300, 314. Robin redbreast, song of, 308. Rocks, of the Catskills, 34, 46, 47. Rondout Creek, 34, 49. Rose, wild, 11, 98. Rudbeckia. _See_ Cone-flower. Sapsucker, yellow-bellied. _See_ Woodpecker, yellow-bellied. Scorpion, 251. Senancour, Étienne Pivert de, quotation from his _Obermann_, 214, 215. Shad, 15. Shad-bush, low, 42. Shakespeare, quotation from, 316. Shelby, Colonel, his form, 225. Shrike (_Lanius_ sp.), and chipmunk, 147, 304-306; song of, 303, 306. Sink-holes, 229, 230. Skunk (_Mephitis mephitica_), a narrow escape, 179; fearlessness of, 196. Skunk cabbage, 162, 219. Skylark, on the Hudson, 210; song of, 210. Slide Mountain, location and description of, 33, 34, 35; ascent of, 37-42; on the summit, 33-54; descent of, 54-56. Snake, black, fight with a pair, 128-130; rifling nests, 128, 130; swallowing a garter snake, 131, 146, 195, 256; as a rattler, 309. Snake, garter, 131; as a rattler, 309. Snake, glass, _or_ joint-snake, 263, 264. Snake, green, 131; protective coloring of, 260, 261. Snakes, spring awakening of, 163; their so-called power of charming, 255-257. _See_ Hair-snake. Snow, on Slide Mt., 54; damage to peach buds caused by, 160; tracks in, 302-304. Snowbird, _or_ slate-colored junco (_Junco hyemalis_), 159. Snowflake. _See_ Bunting, snow. Sparrow, bush _or_ russet _or_ field (_Spizella pusilla_), 119; song of, 165, 167. Sparrow, Canada _or_ tree (_Spizella monticola_), 159. Sparrow, English (_Passer domesticus_), 62, 77, 118, 119, 272, 275; a female assists a chippie in feeding a young cowbird, 315. Sparrow, fox (_Passerella iliaca_), song of, 308. Sparrow, Henslow's (_Ammodramus henslowii_), 296. Sparrow, lark. _See_ Finch, lark. Sparrow, savanna (_Ammodramus sandwichensis savanna_), 296. Sparrow, social. _See_ Chippie. Sparrow, song (_Melospiza fasciata_), 64; building on an insecure foundation, 123, 124, 159; an interesting couple, 187-189; song of, 169, 170, 187, 189; nest and eggs of, 15, 63, 64, 123, 124, 135, 187-189. Sparrow, swamp (_Melospiza georgiana_), 17; nest of, 17. Sparrow, yellow-winged _or_ grasshopper (_Ammodramus savannarum passerinus_), 295-297; notes of, 295, 296; nest and eggs of, 296. Spider, a Javan, 309. Spider, flying, 220. Spring, first days of, 158-160, 218-220.