24 



INDEX 



References are to pages 



Lumbering, in New York (fig.) 380 

 operations, forests destroyed 



by 387 



Lungs 3, 117, 192, 193 



and heart (fig.) 193 



Luxuries, fleshy fruits ... 311 



of food from rose family . 328, 401 



Lymph 203 



Lymphatic circulation . . . 204 

 Lymphatics, superficial, of arm 



and hand (fig.) 204 



M 



Mackerel, a bony fish .... 106 



value of, as food . . . ." . 178 



Maggots, larvae of flies ... 19 



Magnesium, a salt 173 



Magnesium sulphate in Pas- 

 teur solution 356 



Main arteries, of frog (fig.) . 202 



of man (fig.) \ 203 



Malaria 42, 237 



caused by mosquito .... 238 



protozoan disease 234 



Malarial parasite, source of . 238 



Malarial swamp (fig.) . . . 238 



Mallard duck, skeleton of (fig.) 138 



Mallow, family, importance of 329 



flower of (fig.) 331 



Malt, formation of 355 



Mammals, classified .... 7 



discussed 150 



number of 7 



report on 155 



summary of 159 



Man, example of mammal . . 7 

 Mandibles (fig.) .... 13, 14, 41 



Mantle 94 



Map, of corn production . . . 319 



of cotton production .... 332 



of potato production .... 335 



of production of oats .... 324 



of production of orchard fruits 330 



of wheat production .... 325 



Maple, seedlings, cotyledons of . 282 

 development of (fig.) . 279, 280 



syrup 385 



trees, products of 385 



twig (fig.) , . 289 



Maple sugar industry, in Ohio 385 



in Vermont 385 



Marchantia (fig.) 367 



Marsh hawk, partly harmful . 

 Martins, mosquitoes eaten by . 

 Massasauge, a rattlesnake . . 

 Masts, use of gymnosperms for 

 Material for clothing . . . 

 Matter, organic and inorganic 



145 

 42 

 132 

 384 

 329 

 9,10 

 163 



Maturity, a period of life 

 May beetle, injurious insect 



(%•) • • • 26 



May flies, member of order 



Ephemeridae 20 



Meadow lark, food of . . . 147 



nest of 141 



Mealy bug (fig.) 25 



Measles, probable cause of . .234 

 Measuring worms, cater- 

 pillars 19 



Meat 10 



indirect product of plants . . 401 



lean, use of, as food .... 176 

 Mechanical tissues of pteris 



stem 370 



Median fins of fish 107 



Medicinal members of crow- 

 foot family, list of . . . 327 

 Medicines furnished by 



crowfoot family .... 327 



Medulla, of frog 119 



of man 224 



Medullary layer of kidney . 207 

 Medullary rays, in woody 



stem 289 



of pine 378 



Medullary sheath of nerve . 211 



Medusa, described 67 



hydroid (fig.) ....... 67 



pelagia (fig.) 67 



Melons, example of pepo . . . 310 



Mendel, Gregor, study of peas 125 



Mendelian laws, defined . . 126 

 Menhaden, example of bony 



fish 106 



Mental inefficiency, cause 



of poverty 257 



Mercury poison . . . . 221,232 



Mesentery of frog 117 



Mesoglea of coelenterate . . 63 



