20 
INDEX 
References 
Insect enemies of forests . . 358 
Insects, affecting the health of 
domestic animals.... 525 
affecting the health of man . 525 
affecting the health of shade 
trees.525 
carriers of bacteria .... 229 
devices of flowers for attract¬ 
ing .202 
examples of Arthropoda . . 9 
field study of.19 
object in visiting flowers . . 208 
pests.52 
Inspection of meat. . . 177, 500 
Inspiration, defined .... 445 
Insulation of nerve fibers . . 480 
Integument, of bean .... 219 
of ovules.212 
Intercellular spaces . 291, 454 
Internal, gills.92 
organs of frog.85 
lungs.92 
structure of earthworms, 
laboratory study of . . 182 
Intestinal glands.409 
Intestine .408 
Invertebrates, group of animals 8 
Inverted image.474 
Involuntary muscles .... 437 
Iodine test for starch .... 228 
Iris of eye.473 
Iron in blood cells.413 
proportion of, in living things 13 
Irregular flower of violet 204 
Irregular flowers, defined . . 204 
Irritability a fundamental func¬ 
tion .5,6 
Ivy, roots of.252 
Japanese barberry, immunity 
of.388 
Jaw bones of fish.71 
Jaw of man.406 
Jellyfish, example of coelenter- 
ate. 8 
members of hydra group . . 160 
Jenner, vaccination .... 510 
Jewelweed, explosive fruit of 238, 241 
Jimson weed, member of night¬ 
shade family.300 
Joints in man.434 
are to pages 
Juice of mustard family, char¬ 
acteristics of.298 
Juice of the buttercup, char¬ 
acteristics of.297 
Junco. 
at seed station.118 
at suet station.118 
K 
Katydids, a family of Orthop- 
tera.29 
Keel of bird’s breastbone 109 
Keeled sternum of bird . 109 
Keeping well.499 
Kelp, use of.504 
Kernel, comparison with bean 
pod.224 
Kidney, described.458 
Kidneys of frog.87 
Kidneys of man.458 
Kinds of foodstuffs in seeds 228 
Kinds of land used for forests . 356 
King bird.115 
food of.115 
Kingfisher, nesting habits of . 112 
Knees of cypress . . 252, 253 
Koch, discoverer of Bacillus 
tuberculosis.489 
of tuberculosis test .... 316 
study of bacteria by . 316, 489 
L 
Labium.22 
Laboratory experiments with 
leaves.286 
Laboratory study, of bacteria . 312 
of bean seed.227 
of bread mold.325 
of corn.226 
of ferns.337 
of foodstuffs in seeds . . . 228 
of fruits.234 
of grasshopper.20 
of gymnosperms.346 
of leaves for storage . . . 379 
of lily.200 
of live fish.72 
of marchantia.331 
