560 



INDEX 



ture and function of, 180-181 ; move- 

 ment of, 182 ; protection of, 179 ; red 

 corpuscles, 179 ; size, 182 ; structure 

 of, 179 ; volume of air in, 183 



Lymph, circulation of, 165-166 ; fluid, 

 137 ; pressure of, 166 ; source of, 165 ; 

 spaces, 166 ; vessels, 165-166 



Lymph gland, function of, 167 



Lymph nodes, bacteria in, 167 ; func- 

 tions of, 167; position of, 166-167; 

 structure of, 167 



Lymphatic system, 163-169 



Lymphatics, 137 ; functions of, 166-167 ; 

 valves in, 166 



Lysins, use of, 501 ; kinds of, 501 



M. A., 228 



Macronucleus, in Paramecium, 4950 



Malaria, 480-486 ; cause, 482 ; diagnosis 



of, 485 ; history of, 481-482 ; investi- 

 gation of cause, 15 ; method of spread, 



482 ; nature of, 484-485 ; prevalence 



of, 480-481 ; prevention of, 486 ; 



treatment of, 485 

 Malarial parasite, life cycle of, 482-484 ; 



multiplication of, 483-484 

 Malnutrition, cause of, 104 ; effect on 



embryo, 313 

 Malpighi, drawing of circulation by, 151 ; 



movement of blood in capillaries first 



seen by, 164 



Malpighian layer, of skin, 172 

 Malthus, effect of essay on Darwin, 373 ; 



Essay on Population, 343 

 Mammalia, classified, 526-527 

 Mammals, development of embryo, 299- 



300 ; food of, 300 ; infancy, 299-301 ; 



years of dependence, 300-301, 302 

 Man, infancy in, 301-303 ; protection of 



young, 30 

 Manufacture, of food, by green plants, 



36-38 



Marconi, Guglielmo, portrait of, 1 

 Marsupialia, animals of Order, 526 

 Mastication, importance of, 123 ; process 



of, 120 



Mastigophora, 521 

 Mastodon, restoration of, 379 

 Maturation, of egg, 264 ; of sex cells of 



fruit fly, 269 ; of sperm, 264 ; process 



of, 268-270 ; variation due to, 285 

 McCollum, investigation on diets, 93- 



95 

 Measles, after-effects, 478 ; method of 



spread, 478 ; prevention of, 478 

 Measurement, of health, 419 

 Media, definition of bacterial, 395 ; for 



cultivation of bacteria, 396-397 

 Medicine, early practices of, 3, 10-13 

 Medulla, oblongata, description of, 207 ; 



function of, 207 



Membrane, meaning of, 75 ; mucous, 75 ; 

 serous, 76 



Mendel Gregor, experiments with peas, 

 322-326, 327-329; portrait of, 318; 

 rediscovery of writings, 330 



Mendelian laws, of dominance, 322-324 ; 

 of segregation, 324-326 ; of unit 

 characters, 327-330 ; of heredity, sum- 

 marized, 331 



Mental age, 228 



Mental hygiene, 227-237 



Mental poise, cause of lack of, 233-235 ; 

 need of, 227, 233 ; relation to disease, 

 502-503 



Mesentery, function of, 77 



Mesoderm, of embryo, 286 ; development 

 of, 286 ; systems formed from, 286 



Metabolism", basal, 193; in cell, 59-60; 

 kinds, 187 ; meaning of, 59-60 ; of 

 carbohydrates, 188; of fats, 190; of 

 proteins, 188-190 



Metamorphosis, of frog, 287 



Metaphase, stage in cell division, 62 



Metchnikoff, on bacteria of putrefaction, 

 140 ; theory of immimity, 504-505 



Method, modern scientific, 13-15 



Micron, unit of measurement, micro- 

 scopic work, 392-393 



Micronucleus, in Paramecium, 47-50, 248 



Micropyle, of egg, 270, 276 



Microscope, 19-25; care of, 23-24; 

 compound, 20 ; history of develop- 

 ment, 19-20; Hooke's, 27; labora- 

 tory problem on use of, 2426 ; parts 

 of, 21-23 ; rules for focusing, 24 



Milk, acidophohis, 140 ; increase in 

 products of, 344 ; influence on ty- 

 phoid, 467 ; laboratory problem to 

 determine bacterial content, 401 



Minerals, foods containing, 96 ; insuffi- 

 ciency, 95 ; need of, 95 



Mitosis, in animal cell, 6163 ; in plant 

 cell, 63, 64 ; laboratory study of, 63 ; 

 process of, 60-63 



Mitral valve, of heart, 160 



Mold, laboratory problem, on spore 

 formation, 251-252 ; hyphae, 251 ; 

 mycelium, 257 ; rhizoid, 251 ; sexual 

 reproduction in, 264, 265 ; sporangium 

 of, 251-252, 253 



Molecular theory, 35 



Molecules, laboratory problem to show 

 movement of, 35 



Mollusca, classified, 523 ; meaning of, 

 523 



Mollusks, the young of, 296 



Mongolian expeditions, 385-387 



Monotremata, 526 ; duckbill, 513 



Morgan, T. H., on heredity, 55 ; por- 

 trait of, 318; work on heredity, 14; 

 work on mutations in fruit flies, 312 



