4 
INDEX 
References 
Bean — continued 
example of dicotyledons . . 9 
foodstuffs in.228 
fruit of.237 
germination of.220 
seed, laboratory study of . . 227 
seed, relation to flower . . 219 
seedling, parts of .... 220 
source of protein .... 228 
Bean (pulse) family, members 
of.299 
Bean weevil.34 
Beans as food.222 
Beaver.137 
Bee, culture investigations . . 525 
Bee farms, escape of bees 
from.48 
Bee fly, a beneficial insect . . 54 
Beech, value of.297 
Beech family, description of . 297 
Beech leaves.297 
Beef extract, in agar-agar . . 312 
Beer, use of yeast in making . 321 
Bees, classes of.46 
classified insects. 9 
complete metamorphosis of . 28 
drone.46 
gathering of nectar and pollen 
by.208 
honey, value of.49 
imperfect female (worker) . 46 
life history of. 46 
members of Hymenoptera . 29 
nurses.46 
perfect female (queen) . . 46 
swarming. 48 
wax, value of.49 
Beet, a dicotyledon .... 227 
biennial plant.252 
source of sugar.255 
storage of food in ... . 255 
Beetle, May, a harmful insect . 34 
potato, a harmful insect . . 35 
Beetles. 34 
bird enemies of.35 
example of complete meta¬ 
morphosis .28 
Belladonna, compared with 
stramonium.300 
source of.300 
Belly of muscle.438 
are to pages 
Berkshire pigs.133 
Berry, a form of fruit . . 233, 237 
collection of drupes.... 239 
defined.233 
Biceps muscle.438 
Bichloride of mercury, use of . 512 
Biennial roots.252 
Bilabiate flowers of mint . . 300 
Bile, a digestive juice .... 412 
Binding effect of roots . . . 256 
Biological diseases, kinds of . 488 
Biological problems involved in 
the production of food . . 420 
Biological survey.526 
Biological terms defined ... 1 
Biology and human progress 521 
Biology, defined. 6 
progress of.521 
Birds, characteristics of . . . 107 
classified. 9 
economic importance of . . 114 
number of. 9 
summary of.124 
Bird’s-eye maple.352 
Bird’s feet, different kinds of . 108 
Bitter, a fundamental taste . . 405 
Bittern, beak of.109 
Bivalves, reason for name . . 189 
Blackberry, in plant succession 375 
receptacle of fruit eaten . . 239 
Blackbirds, food of 35, 43, 115 
Black snake, a constrictor . . 102 
Black mustard.223 
Black raspberries.272 
Black rot. 531 
Black stem rust.... 380, 384 
Black walnut lumber .... 352 
Bladder in man.458 
Blade of leaf, food storage in . 276 
Blanching of celery .... 293 
Bleeding in plants.269 
Blood, corpuscles. 449 
of man. ’ . . . 449 
plasma. 449 
pressure in man. 454 
supply of muscle .... 438 
vessels, function of . .451 
Bluebird, a beneficial bird . . 114 
destroyed by hawks . . . 115 
destroyer of Lepidoptera . . 42 
food of. 144 
