tion, prothallium, 122.

Hound's-tongue, 215; Fig. 119.

_Houstonia_, 223; Fig. 124.

_Hoya_. See "Wax-plant."

Huckleberry, 181, 211; Fig. 116.

Humming-bird, 226.

Hyacinth, 146.

_Hydnum_, 84; Fig. 51.

_Hydrangea_, _-geae_, 202; Fig. 111.

_Hydrocharideae_, 167.

Hydrogen, 2, 95.

_Hydropeltidinae_, 189.

_Hydrophyllum_, _-aceae_. See "Water-leaf."

_Hypericum_, _-aceae_. See "St. John's-wort."

_Ilex_. See "Holly."

_Impatiens_. See "Jewel-weed," "Balsam."

India-rubber, 200.

Indian-pipe, 144, 210; Fig. 79.

Indian turnip. See "_Arisaema_."

Indusium, 118.

Inflorescence, 157.

Integument, 133, 144, 151, 180.

Intercellular space, 124, 135, 150.

Internode, 39.

Iodine, 4, 22, 31.

_Ipomoea_, 213.

_Iridaceae_, 156.

Iris, 154, 156; Fig. 84.

Irish moss, 49.

_Isocarpae_, 210, 212.

_Isoetes_. See "Quill-wort."

_Iuliflorae_, 181.

Ivy, 202.

Jack-in-the-pulpit. See "_Arisaema_."

Jasmine, 218.

_Jeffersonia_. See "Twin-leaf."

Jewel-weed, 197; Fig. 107.

Joint fir, 140, 142.

_Juncagineae_, 167.

_Juncus_. See "Rush."

_Jungermanniaceae_, 92; Fig. 57.

_Kalmia_. See "Mountain laurel."

Karyokinesis, 233.

Keel, 208.

Kelp. See "_Laminaria_."
giant. See "_Macrocystis_."

Knotgrass. See "_Polygonum_."

Labellum. See "Lip."

_Labiatae_. See "Mint."

_Labiatiflorae_, 215.

Lady's-slipper, 164, 166, 198; Fig. 90.

Lamella, 83.

_Laminaria_, 45, 47; Fig. 28.

_Lamium_. See "Dead nettle."

Larch. See "Tamarack."

_Larix_. See "Tamarack."

Larkspur, 186, 227; Fig. 99.

Latex, 191.

Laurel, 188.

_Laurineae_. See "Laurel."

Lavender, 215.

Leaf-green. See "Chlorophyll."

Leaf tendril, 171.

Leaf thorn, 172.

_Leguminosae_, 207.

_Lemanea_, 53; Fig. 31.

_Lemna_. See "Duck-weed."

Lemon, 198.

_Lentibulariaceae_, 217.

Lettuce, 223.

_Lichenes_, 73; Figs. 44, 45.

Ligula, 127.

_Ligulatae_, 125.

Lilac, 170, 181, 218.

_Liliaceae_, 155.

_Liliiflorae_, 153, 155; Fig. 83.

_Lilium_. See "Lily."

Lily, 146, 155.

Lily-of-the-valley, 155.

Lime. See "Linden."

Linden, 195; Fig. 106.

Linear, 159.

_Linum_, _-aceae_. See "Flax."

Lip, 165.

_Liriodendron_. See "Tulip-tree."

_Lithospermum_. See "Puccoon."

Liverwort, 86.
classification of, 91.
horned. See "_Anthoceroteae_."
giant, 91; Fig. 57.

Lizard-tail, 181, 183; Fig. 97.

_Lobelia_, _-aceae_. 221; Fig. 123.

_Logani