r-NRLF B 3 7DT LIBRARY OF THE UNIVERSITY OF CALIFORNIA. GIFT OF UBRARY LABORATORY MANUAL FOR THE SOLUTION OF PROBLEMS IN BIOLOGY BY RICHARD W. SHARPE INSTRUCTOR IN BIOLOGY IN THE DEWITT CLINTON HIGH SCHOOL NEW YORK NEW YORK-:- CINCINNATI •:• CHICAGO AMERICAN BOOK COMPANY S4 BIOLOGY LIBRARY G " To know nature and man is the sum of all earthly knowledge." — G. STANLEY HALL. "The work of the high school should have for its central aim the helping of pupils to be helpful in the home and community here and now. . . . Every bit of science and every bit of literature should be taught with such ends in view." —A. W. BALDWIN. " Half a million lives are cut short and five million people are made ill by preventable diseases each year. With universal knowledge of hygiene and sanitation nearly all deaths from such causes could be prevented." — HOUSEHOLD EDUCATION LEAGUE. COPYRIGHT, 1911, BY RICHARD W. SHARPE. ENTERED AT STATIONERS' HALL, LONDON. SHARPE'S LABORATORY MANUAL. w. P. 1. PREFACE MOST teachers of biology in secondary schools to-day aim to emphasize the biological relations of plants and animals from a physiological standpoint. The practical aspect is also becoming more and more recognized as most desirable, as opposed to the strictly educational and cultural functions of this subject. Moreover, it is being gradually brought to our attention that methods of study that induce thinking are of far more import than any attempts at mere memorizing.1 Hence we have what may be called the "Problem Method" of study and class exercise. With these considerations in mind, I have attempted to de- velop a series of solutions of problems in biology. These prob- lems are intended to be prim aril}7 physiological in their import, but with especially significant references made to man at every opportunity. I am confident that this method of treatment will not be interpreted as being too utilitarian, although the relations of plants and animals to man are by no means lightly dwelt upon. "Of all the pleas that Spencer2 makes for the sciences, that for physiology is the most convincing, for the problems of hygienic living are always personal and persistent, as are those that pertain to food, stimulants, nar- cotics, clothing, and shelter. . . . Consequently, the teacher is to be pardoned if he urges the practical, rather than the strictly educational, function of this study." 3 It appears to be generally admitted that a course in sec- ondary school biology should include training in logical think- 1 See McMurry, How to Study, Chaps. III-VII, for splendid treatment of this phase of educational processes. 2 Education, Chap. I. 3 De Garmo, Principles of Secondary Education, p. 87. 3 4 PREFACE ing and exactness, orderly and neat procedure, general culture, etc. At the same time it seems to be expected that we should include references to food, clothing, shelter, health and sex hygiene, morals, and aesthetics. Such a combination is not impracticable, and yet there does not seem to exist any method whereby such matters may be handled as problems in our secondary schools. The attempt to work out such a method has supplied my immediate motive for compiling this book. Some special arrangements of matter should be noted: First, the solutions are mostly provided with questions arid special reports for both class and home work. Second, a list of references for the special reports is added, commonly to topics of human interest not to be found in the ordinary texts in biology. It is suggested that pupils be encouraged to be constantly on the lookout for pertinent articles on biological topics such as may be found in good magazines, the better daily papers, etc. These should be culled and card catalogued. Constant reference is also made to Hunter's Essentials of Biology, a volume which this manual is especially intended to accompany. Third, the larger type indicates matter which is regarded as most important. Teachers are expected to cull that which fits the problems nearest at hand. No classes can be expected to cover all the ground outlined in one year. The smaller type indicates matter which is supplementary and optional, depending on the locality, material on hand, and special interests of both teachers and pupils. Much matter is also included to permit abler and more advanced students to choose work that is not being regularly undertaken by the entire class. Many new texts and manuals have been freely consulted in preparing this manual. Special thanks are due to Dr. W. H. Eddy and Mr. C. W. Hahn 'of the High School of Commerce, New York, Dr. H. E. Walter of Brown University, Miss A. P. Hazen of the Eastern District High School, New York, and Mr. G. W. Hunter of the De Witt Clinton High School for many helpful suggestions concerning the manuscript; to PREFACE 5 Dr. Irving Fisher of Yale University, the American School of Home Economics of Chicago, and the Journal of the Ameri- can Medical Association for certain food studies ; to the Mer- chants' Association of New York for material concerning the house fly; to Dr. W. H. Allen, Secretary of the Bureau of Municipal Kesearch of New York for suggestions and certain statistics concerning infant mortality; to Mr. J. J. Schoon- hoven for the loan of several cuts ; and to my wife for much assistance with the many details of construction. Construc- tive criticisms and suggestions for improving this manual will be most cordially welcomed. E. W. SHARPE. DEWITT CLINTON HIGH SCHOOL, NEW YORK. " The present trend of education seems to be to make these three subjects — the home, agriculture, and industry — the basis of universal, democratic education." SUGGESTIONS FOR USING THIS MANUAL Observations, — In the first place, pupils of first or second years in secondary schools have too limited an experience to permit of their being left to their own devices. All observa- tions, therefore, should be made in small installments as imme- diate answers to certain leading questions which pupils should be encouraged to ask for themselves. Pupils are to be graded on their ability to see, at the time they observe, and as orally expressed. " Seeing true means thinking right. Eight think- ing means right action. To bring about right action is the end of Science. Lack of precision in action is the greatest cause of human misery, for misery is nature's protest against the results of wrong conduct." Optionally, at times, their observations may be written before being orally expressed. Other pupils may be encouraged to criticise any incomplete or wrong observations, until it is evident to all that the neces- sary observations are as carefully and completely made as is possible with the facilities at hand. Conclusions. — All pupils are now to write out their own conclusions, as based on the observations made. (Optionally they may be recited, depending on the matter under consid- eration.) A limited time is given in which to write their conclusions, then a number read and criticised until the class individually and as a whole grasps the significance of the observations made and the logical deductions therefrom. Such conclusions are also to be graded at the time, thus bringing about much closer supervision of the work than would other- wise be possible, and with the added and very important advantage of avoiding much of the senseless clerical drudgery of looking over notes. Mistakes are thus corrected at a time when such corrections are the most effective. 6 CONTENTS Optional problems are indicated by a star (*). , PAOB DIRECTIONS TO THE STUDENT .-'/.. . . . . . 11 THE NATURE AND NEEDS OF LIVING MATTER PROBLEM I. A study of the common elements in the environment of living things ... . .... 17 * II. Are mineral matter and water present in living things ? . 23 III. A study of the different groups of foods (nutrients) which living organisms need, and how to detect their presence. 23 IV. An introduction to the nature and work of living organ- isms .- .. . . • . . •-.'•'. . . 27 (* EXERCISE) A study of the construction and use of the compound microscope . . . . . .... '• . 32 V. The structure and general properties of living matter . 35 PHYSIOLOGICAL PROCESSES AND ADAPTATIONS IN PLANTS VI. The structure and work of the parts of a simple flower . 40 VII. A study of cross-pollination and some of the means of bringing it about . . ."' . . ' . - *. . 43 i VIII. A study of fruits . . . . . . . . 48 IX. The economic value of some fruits . , . . ; . 52 X. A study of seeds in their relation to the new plant . . 55 XI. A study of the conditions (factors) necessary for awaken- ing (germinating) the embryo in the seed ... 59 XII. A study of young plants until they are independent (seed- lings) . . . . . • ':. _ . '•.'•••.' • . . 61 * XIII. A study of some methods of plant breeding ... 64 XIV. A study of the structure and work of roots ... 73 XV. A study of some of the relations between roots and the soil 78 * XVI. A study of buds and their relation to the growing plant 89 XVII. The structure and work of stems 90 XVIII. A study of leaves in relation to their environment . . 95 *XIX. Some uses of stems . 106 7 CONTENTS *XX. Some forms of plant life, with special reference to nutrition and reproduction . . . . .111 * XXI. A study of the ways plants are modified by their sur- roundings ..,.«>. * . . 110 THE BIOLOGICAL INTERRELATIONS OF PLANTS AND ANIMALS XXII. Some relations of fungi to man . . •? <- . 123 XXIII. A study of bacteria and of some of their relations to man . . . . -. V -;. - . ' :.. . 125 XXIV. A study of some biological relations of plants and animals ., - • ,* . .. '. • . ••• . 133 THE PHYSIOLOGICAL UNIT AND DIVISION OF LABOR XXV. To study a one-celled animal, in order to understand better the unit of animal structures . . » • . 140 XXVI. An introductory study of many-celled animals (Met- azoa) . . . ... . , ••;'• - ' . 143 SOME REACTIONS AND ADAPTATIONS AMONG ANIMALS * XXVII. The relations of the earthworm to its surroundings . 151 XXVIII. A study of some animal associations .... 153 *XXIX. A study of the idea of adaptations as shown in the crayfish .... ^. . . . .162 THE MOST SUCCESSFUL ANIMALS, INSECTS, AND THEIR RELATION TO MAN XXX. A study of some animal likenesses and differences, and the classification of insects 170 XXXI. How insects became winners in life's race . . . 179 XXXII. Some relations of insects to man 182 THE BIOLOGICAL RELATIONS OF SOME AQUATIC FORMS OF LIFE XXXIII. A study of mollusks with special reference to their economic importance . . . • • .194 CONTENTS XXXIV. A study of how a live fish is fitted for the life it leads 195 * XXXV. A study of some of the relations of fishes to their food supply . . : . .... .... . 199 « XX XVI. The artificial propagation of fishes . ... . 202 THE STUDY OF THE FROG AS AN INTRODUCTION TO MAN XXXVII. Some adaptations in a living frog, as an introduction to the study of man . . . . ? . 204 XXXVIII. A study of the development of the frog . « . 207 BIRDS IN THEIR RELATION TO MAN XXXIX. A study of some adaptations and reactions in birds . 211 XL. How birds are of economic importance . . . 213 THE HUMAN BODY AS A MACHINE XLI. A study of man as a vertebrate, as compared with a frog . . .218 FOODS AND DIETARIES XLII. A study of food values and diets . . . . 226 XLIII. A study of some forms of food adulteration, and some simple means of detecting them . . . 251 XLIV. A study of some medical frauds . . « . . 255 ADAPTATIONS FOR DIGESTION, CIRCULATION, AND ABSORPTION OF FOODS XLV. A study of the digestive system of a frog in order bet- ter to understand that of man . '. . . 267 XLVI. How foods are chemically prepared for absorption into the blood . - ...;."'.; . . . . 271 XL VII. A study of where and how digested foods pass into the blood (absorption) . ... . . 277 XLVIII. To study the general composition of blood . . 281 '. XLIX. A study on the circulation of the blood . . . 282 L. Some changes in the composition of the blood . . 289 10 CONTENTS ADAPTATION FOR RESPIRATION AND EXCRETION PROBLEM PAGE LI. A study of the organs and process of respiration , . 291 LII. A study of the products of respiration . . . . 296 LITE. A study of ventilation . . . ' . * . . * . 299 LIV. Part I (Experimental). To study some of the functions of the skin of man . . . . -.',.. . 305 LIV. Part II (Summary). A final study of the changes in the composition of the blood as it passes through various organs of the body .... . .' . 308 NERVES AND THEIR CONTROL LV. A study of the nervous system, reactions to stimuli, and habit formation . . '. . . . . . . . 312 PERSONAL AND CIVIC HYGIENE LVI. A study of personal and civic hygiene . ?..'"-;•." . 320 DIRECTIONS TO THE STUDENT FOR KEEPING NOTES IN BIOLOGY NOTEBOOKS are to be brought to every biology period. The notebook, when completed, should contain a record of your daily work, not only the exercises performed in the laboratory, but all home experiments, field excursions, and any other work that is your own original observation. The notebook should not contain any copied drawings, dictation notes, or other matter not original with you, unless you specify that such work was copied. The authority from which such copied work is taken should also be noted. Exercises written in the laboratory should be written on the ruled paper provided; drawings should be placed on the unruled paper. One side of the paper only may be used, except in the case of home work written in ink, in which event both sides of the paper may be used. Use a well-sharpened hard pencil (HHHHH) for all draw- ings made in the laboratory. Prepare your papers for notes, drawings, and experiments according to the model forms given you in the pages following. Place your name, class number, the date, and the title of the exercise in the spaces reserved for this purpose on each sheet of paper used. Place also your name, the date, and the title on every piece of home work handed in to the teacher for correction. Number the notes, answers to questions, or any written para- graphs to the left of the vertical line. Number the pages of all your work, and keep dated work in the proper order before handing it in to be criticised by the teacher. Especial care should be taken with your drawings. Your hard pencil should be sharpened to a needle-like point. Many 11 12 DIRECTIONS TO THE STUDENT drawings are rejected simply because the pencil was too dull for you to bring out the structures you wanted to show. Every line you make on the paper should mean something. Draw with a firm, bold, continuous stroke. Do not sketch. Do not try to shade, unless you are an artist. Use the scale indicated in your laboratory directions : thus X 2 means that your drawing is to be made twice natural size. Learn to use the metric system in making your estimates of distance, weight, etc. Above all things be accurate, careful, and neat. Fifty pages of notes and drawings carefully prepared are worth more than one hundred placed carelessly or hastily on the pages. Your laboratory exercises are in part a training for more accurate and careful science work in the later years of the high school and in college. This is the time and the place for you to learn how to do scientific work, and scientific work is synony- mous with accuracy and carefulness. 13 Date Title of Laboratory Exercise Name of pupil In this space you should place all written observations made in the laboratory. This includes all notes and answers to ques- tions ; the questions and directions, however, should under no circumstances be written, they are simply for your guidance. In the space between the two red lines to the left of the page should be placed the number of the answered question. Do not place any drawings on this ruled sheet. This paper may also be used for all home work, accounts of excursions, etc. 14 Bate Title of Drawing Name of pupil Place your drawing or drawings in this space so as to make a symmetrical arrangement. If only one drawing is made, then place it a little to the right of the middle of the page, remem- bering that about an inch of the left edge of your page is lost in the binding together of the sheets. Every part of the drawing should be named by means of a series of labels. Indicate each part or structure that you wish to call attention to by means of a broken line running from the part to be labeled outward on the paper outside the drawing. At the outer termination of this line place either a number or a letter which will be repeated in the index below and which will there serve to identify the part shown in the drawing. Indicate exactly where the other end of the dotted line ends by a tiny cross. The index or table of contents at the foot of the page should be neatly printed ; if possible, an equal number of figures or letters should be placed on each side of the vertical line which divides the index into a right and left half. If the number of parts labeled in the drawing is unequal, then the last or odd label should be placed in the space at the bottom of the divid- ing line, thus insuring a neat and symmetrical page. Index or Table of Contents OF THE UNIVERSITY ] 15 OF Date Title of Experiment Name of pupil Problem. — State here exactly the question you are trying to solve. Method. — In this space place all the data with reference to setting up the experiment. Describe all the apparatus used, how you put it together, and how you made use of each part. Observations. — In this space you should place all observations made upon the experiment from the time of beginning to the time of ending the experiment. If the experiment takes several days to complete, it will probably be necessary to record your observations in a pocket notebook in rough form and later copy it in this space. All details should be put down at the time the observations are made ; do not wait until a later time to write up the details, which may easily be forgotten and which may affect the accuracy of the observations you have made. Be sure to indicate in your written notes any unusual occurrences which might influence the final results of the experiment. Such might be a sudden drop in temperature, the drying of seeds, etc. Conclusions. — In this space place your statement of the solu- tion of the problem you have been working upon. This conclu- sion should be stated in concise, scientific terms. Be sure you understand your problem exactly before you attempt a solu- tion ; this may take considerable time and thought on your part. Date 16 Title of Experiment Name of pupil In this space should be placed a drawing of the ap- paratus set up at the begin- ning of the experiment. In this space should be placed a drawing showing your apparatus at the com- pletion of your experiment. Be careful to show all changes which take place in the ap- pearance of the materials used in this as compared with the first stage of your experiment. Index or Table of Contents THE NATURE AND NEEDS OF LIVING MATTER PROBLEM I A study of the common elements in the environment of living things- a. Nitrogen (N) and the Composition of the Air Note. — The most abundant elements in living matter are carbon, hydrogen, oxygen, and nitrogen. Apparatus. — Large deep dish of water, bell jar or large wide-mouth bottle, large cork, and phosphorus. Method. — Cut off a bit of phosphorus as large as a pea, and float it on the large piece of cork. Ignite it, and cover it quickly with the bell jar. Observations. — 1. Does the water rise in the bell jar? If so, how high ? 2. What was in the bell jar as it was inverted over the phosphorus ? Note. — The phosphorus unites in burning with an element in the FlG" r T Gettillg ^percent- ° age of nitrogen in the air. air called oxygen, and forms a sub- stance (fumes) which dissolves in the water present. Conclusions. — 1. What formerly occupied the space now filled with water ? What part of the original contents of the jar was oxygen ? 2. If the phosphorus used all the oxygen in burning, about what part of the air must be oxygen ? (The rest is mostly nitrogen.) SHARPE'S LAB. MAN. — 2 17 18 THE NATURE AND NEEDS OF LIVING MATTER 3. Does nitrogen support burning (combustion) ? Note. — The air is composed mostly of oxygen and nitrogen, plus small amounts of water vapor, carbon dioxide, argon, etc. b. Oxygen (0) and Oxidation Apparatus. — Test tubes, potassium chlorate, black oxide of manganese, alcohol lamp or Bunsen burner, bent glass tube, 1-holed rubber stopper to fit test tube, wide-mouth bottle, dish of water. General Method. — Heat half a teaspoon- ful of the chlorate of potash with slightly less than the same amount of black oxide of manganese. The resulting gas may be collected over water as indicated in Figure 2, or the tests may be made in the test tubes in which the oxygen is made. Method a. — Light a splinter of wood, blow out the flame, but see that the end is still glowing. Plunge the glowing end in a test tube in which oxygen is being set free. Observations. — 1. What happens to the glowing coal ? 2. What difference between the burning of the splinter in air and in oxygen ? Note. — When oxygen combines with any substance, heat is always released. The process is named oxidation. The sub- stance with which the oxygen unites is said to be oxidized. The element or substance oxidized in this case is carbon. FIG. 2. — Making and collecting oxygen, t, test tube; e, delivery tube; n, chemicals; 0, oxy- gen collecting. THE NATURE AND NEEDS OF LIVING MATTER 19 Conclusions. — 1. How could you determine the presence of oxygen in some substances ? 2. How account for any differences in the oxidation of the splinter in air and in oxygen ? Note. — The burning of the splinter, accompanied by flame, is an example of rapid oxidation or combustion. Method b (Home Exercise). — Place an iron nail in a small bottle filled with water. Cork and seal the bottle. Place another iron nail in a shallow vessel containing a little .^vater. Examine the nails from time to time. Which nail is most exposed to oxygen ? Observation. — Which nail has changed in appearance the most ? In what way ? Note. — The rusting of iron means its union with oxygen to form iron oxide, etc. Since no flame is present, this is an ex- ample of slow oxidation. Conclusions. — 1. What is the process of rusting ? 2. If heat is one result of oxidation, where does the heat of your body come from? Is this rapid or slow oxidation? FIG. 3. -Diagram of rapid oxidatiou TT . _ „ ,_T1 • or combustion in a stove. Heat is a torm ot energy. Why oxidize coal in a locomotive furnace ? 3. What is the relation between rapid oxidation and the release of energy ? Would slow oxidation be satisfactory in a locomotive ? Is rapid oxidation necessary in our bodies ? Explain. c. Hydrogen (H) (Optional) Note. — This element is present in all foods, and composes two thirds of water by volume. Apparatus. — Iron nails or tacks, weak sulphuric acid, wide-mouth bottle, small glass tube drawn to a point and placed in a 1-holed rubber stopper that fits the bottle. Oxygen in the air V 20 THE NATURE AND NEEDS OF LIVING MATTER Method. — Put some nails or tacks in the bottle and cover them with the weak sulphuric acid. Insert cork and delivery tube as in Figure 4. Permit the gas to escape for a short time, wrap the bottle in a cloth, and try igniting the escap- ing gas. Note. — The iron pushes off a gas (hydrogen), w which was a part of the acid. It appears as bubbles and passes out of the glass tube. Conclusions. — 1. Does hydrogen burn (oxi- dize) ? What is the result ? 2. What collects on a tin cup half filled with water held at the top of the flame ? 3. With what does hydrogen unite when it burns ? 4. What is the result of this union ? d. Carbon (C) and Carbon Dioxide (C02) Apparatus. — Piece of wood charcoal, soft coal, clay pipe, shavings, clay, alco- FIG. 4. -Making hydro- ho1 lamP Or BuDSen burner, wide-mouth gen. 10, cup half bottle, limewater, sugar or starch, test filled with water, as tubes. a condensing agent. Method a. — Put some bits of wood in the clay pipe and closely cover them with the clay which has been wetted to form a pasty cover, and heat the pipe very hot for a few minutes. Try to light any gas that may issue from the stem of the pipe. Observations. — 1. What is the color of carbon in charcoal ? Is the carbon in the pipe like that in the charcoal stick ? 2. How does the carbon separated out in the pipe compare with that in the charcoal stick ? 3. What happened when a lighted match was held where the gases were escaping ? Note. — Gas for lighting houses was formerly made in a similar way by heating soft coal in iron boxes. Conclusions. — 1. What is one of the elements in wood ? 2- How does carbon differ from oxygen ? THE NATURE AND NEEDS OF LIVING MATTER 21 Method b. — Heat some sugar and some starch in separate test tubes. What results ? Conclusions. — 1. Do they contain carbon ? Reasons? 2. What do you think is indicated when certain foods are scorched ? 3. Name some foods that you think must contain carbon. 4. How, do you infer, does the human body ob- tain a supply of carbon ? Method c. — Burn a bit of charcoal (carbon) in the wide-mouth bottle, then add P -, /. i . FIG. 5. — Separating wood into gas and two spoonfuls of hmewater charcoal (cParbon)g p> clay pipe8contain. and shake the bottle. ing bits of shavings and covered with Observations. — 1. Is the wet clay; I, flame made by lighting the carbon entirely consumed ? gas as [t issues from the stem' 2. Is there any change in the limewater ? Note. — It is known that nothing but carbon dioxide will cause limewater to become milky. Carbon dioxide is formed by a chemical union of carbon with oxygen. It is really an oxide of carbon. (See Prob. I, &, for further notes.) Conclusions. — 1. How is carbon dioxide formed? 2. What is the test for the presence of carbon dioxide ? Method d. — Breathe through a tube into some limewater. Result ? Conclusions. — 1. What do you decide must be one of the substances that comes from the lungs ? Reasons ? 2. How must this substance have been formed ? 3. What must be one of the elements in the human body ? Questions 1. Can you think of any advantage in the presence of nitrogen in the air? 22 THE NATURE AND NEEDS OF LIVING MATTER 2. If nitrogen can be obtained from the air only by certain plants, how must animals get it ? 3. What part of the air is oxygen ? Nitrogen ? 4. What are the most abundant elements in living matter ? 5. Where may carbon be found ? 6. What results from the electrolysis of water ? 7. Why does excluding air from a fire cause it to go out ? 8. What is the object of a draft in furnaces ? 9. Why does a blacksmith use a bellows in forcing air (oxygen) into the fire ? 10. Why do we breathe more rapidly when we run or work hard? 11. Try to explain what happens when you strike a match. Note. — The head of the match contains phosphorus, sul- phur, etc. 12. What method did the savages formerly use in starting a fire ? Explain. 13. If oxidation also produces energy, or the ability to do work, where does the energy of the locomotive come from ? Of the body ? 14. How is the body supplied with fresh portions of carbon? 15. How would you test for the presence of carbon dioxide ? 16. Sum up as many results of oxidation as you can. Special Reports1 1. The importance of water to living things. 2. The manufacture of charcoal and illuminating gas. 3. The chemical elements in the body. 1 Instead of having such reports always read in class, let the pupil give a talk on his chosen topic. Such talks should, of course, be carefully thought over beforehand. This gives very good practice in oral presentation. Optionally, written reports may be handed in at times. THE NATURE AND NEEDS OF LIVING MATTER 23 PROBLEM II (Optional) Are mineral matter and water present in living things? a. Mineral Matter Method. — Light a splinter and let it burn up as completely as possible. Observations. — 1. What part of the wood have you learned is oxidized in burning ? 2. Is there any portion not oxidized, or left behind as a solid, during the process ? What is this substance commonly called ? Note. — This consists of mineral matter. 3. Burn a piece of meat in a test tube. What remains that will not burn ? Note. — Nearly one half of bone is made of compounds of lime. More than a teacupful of common salt is distributed throughout the body. Enough iron to form a piece as large as a copper cent is found in the blood, liver, and hair. 4. Burn some loam or humus in a test tube. Result ? Conclusions. — 1. What may be found in living things ? 2. What do you think is at least one use of the mineral matter in an animal body ? 3. Where do you think plants get their mineral matter? Where do animals get theirs ? b. Water Method. — Weigh a piece of meat, an apple, and a potato. Peel the apple and potato. Put all in a place where they will thoroughly and quickly dry out. Reweigh. What loss of weight in each case ? Conclusions. — 1. What causes this loss ? 2. Compute the percentage of loss in each case. Note. — Most foods are more than one half water. About 65 per cent of the human body is water. 3. Can you think of any uses of water to animals and plants ? PROBLEM III A study of the different groups of foods (nutrients} 1 which living organisms need, and how to detect their presence. 1 The nutrients may be classified as, 1. Proteids (albuminous or nitroge- nous foods). 2. Fats and oils. 3. Carbohydrates (sugars and starches). 4. Mineral matter. 5. Water. (Water is often classed with mineral foods.) 24 THE NATURE AND NEEDS OF LIVING MATTER a. Starch Materials. — Corn starch, iodine solution, and test tube. Method. — Crush the starch, and add a third of a test tube of water to a bit as large as a pea. Add a few drops of iodine solution.1 Observation. — What change in color do you note ? Note. — If a large amount of starch is present, the material will turn black ; if a smaller amount, it will turn a deep blue. b. Grape Sugar Materials. — Glucose or grape sugar, 2 Fehling's solution or preferably 3 Benedict's second solution, test tubes, and alcohol lamp or Burisen burner. Method a. — Dissolve some glucose in water in a test tube. Add a few drops of Fehling's solution and boil. Observation. — What change in color do you observe ? Note. — If grape sugar is present in any substance, the contents of the tube will change to a yellowish, deep orange, or brick-red color. 1 Iodine solution may be made by adding a few crystals of iodine to enough 95 per cent alcohol to dissolve it well. Or to 1 gram of iodine crystals, add | gram of potassium iodide, and dilute to a dark brown color in 30 per cent alcohol. 2 Fehling's solution may be made as follows : Add 35 g. of copper sul- phate to 500 cc. of water. Solution No. 1. To 160 g. caustic soda (sodium hydroxide), and 173 g. Kochelle salt, add 500 cc. of water. Solution No. 2. For use mix equal parts of solutions 1 and 2. This may also be obtained of druggists, in tablet shape, — or address Jno. Wyeth and Bros., Phila- delphia. 3 Benedict's second solution. — Copper sulphate 17.3 grams. Sodium citrate 173.0 grams. Sodium carbonate (anhydrous) 100.0 grams. Make up to 1 liter with distilled water. With the aid of heat dissolve the sodium salts in about 600 cc. of water. Pour through filter paper into a glass graduate and make up to 850 cc. with distilled water. Dissolve the copper sulphate in about 100 cc. of water, and make up to 150 cc. with distilled water. Pour the carbonate citrate solution into a large beaker and add the copper sulphate solution slowly with constant stirring. THE NATURE AND NEEDS OF LIVING MATTER 25 Method b. — Add 5 cc. of Benedict's second solution to about 8 drops of the solution under examination ; such as the glucose solution. Boil the mixture for one or two minutes and let it cool slowly. Observation. — What changes in color do you notice ? Note. — If grape sugar is present the liquid will be filled with a precipi- tate, which may be red, yellow, or green in color, depending upon the amount of sugar present. The positive test is the precipitate, not the color. c. Fats and Oils Materials. — Nuts or animal fat, white paper, watch glass or other shallow vessel, and ether, chloroform, or benzene. Method a. — Rub the nut or material to be tested on a piece of paper, and hold to the light. Observation. — What effect do you notice when the nut is rubbed on paper ? Note. — If oil is present, a translucent grease spot will appear. Method b. — Put the substance to be tested on a piece of plain white paper and put it in a warm place, as on a radia- tor or in an oven. What happens when nuts are so tested ? Method c. — Grind or crush the substance to be tested, as flaxseed; place it in a watch glass, add ether or benzene, and allow it to stand until it evaporates. Observation. — Do you note anything sticking to the sides of the vessel ? Note. — Ether, etc., dissolves and extracts oils from substances, and on evaporation leaves the oil on the container. d. Proteids or Nitrogenous J Foods Materials. — Raw and hard-boiled white of egg, feather or leather, nitric acid, ammonia, test tubes, spirit lamp. Method a. — Place the substance to be tested in a test tube, and add a little strong nitric acid. Note any color that ap- 1 Nitrogenous foods contain nitrogen, other foods do not. Good examples are peas, beans, white of egg, cheese, and lean meat. 26 THE NATURE AND NEEDS OF LIVING MATTER pears. Rinse out the acid with, water, and add a little ammo- nia, and again note any change in color. Observations. — 1. What change in color when the acid is added ? Note. — If a lemon-yellow color appears, it indicates the presence of proteid. 2. Is there a still further change in color when the ammonia is added ? Note. — A deep orange color now appearing verifies the presence of proteid. Method b. — Put some raw white of egg in a test tube, and heat it. Observation. — What happens as the white of egg is heated ? What change in color? Note. — Any substance thickening and becoming white in color is said to coagulate, and indicates proteid in the form of an albumin. Method c. — Burn a piece of leather, or meat, or feather. Observation. — Note the peculiar odor of burning feather or leather. This shows the presence of a proteid. e. Mineral Matters (Optional) Method. — Burn a piece of meat in a spoon or shovel until no further change can be brought about by heat. Observation. — What seems to be left in the spoon ? Describe it. f. Water (Optional) Method. — Weigh the substance to be tested, as an ounce of meat. Put it aside in a warm dry place, until it is thoroughly dry, and then reweigh it. Observations. — 1. What is the loss in weight of the meat ? 2. What is the cause of most of the loss ? g. Summary Conclusions. — 1. a. What do you conclude is a good test for the presence of proteids in a substance ? b. Of fats and oils ? c. Of starch ? d. Of grape sugar ? (e. Of mineral mat- ter? / Of water?) 2. Explain just what the test consists of in each case. THE NATURE AND NEEDS OF LIVING MATTER 27 Home Work (Optional*). — Apply the above tests to potato, eggs, bread, butter, and beans, and tabulate your results as follows : — • POTATO EGGS BREAD BUTTER BEANS Proteids Fats and Oils . . . . Starch . . i . . . Grape Sugar Minerals "Water Put a check in the above tabulation wherever a nutrient occurs in any of the foods listed for testing. Does any one of the above foods contain all of the nutrients ? Questions 1. What is a food ? 2. Name the nutrients in foods. 3. Give some examples of each of the nutrients. 4. Where do plants get their nutrients ? 5. Where do animals get theirs ? 6. How test for the different nutrients ? References Hunter, Essentials of Biology. Chap. II. American Book Company. Hunter, Elements of Biology. Chap. II. American Book Company. Davison, The Human Body and Health (Advanced). Chap. V. American Book Company. PROBLEM IV An Introduction to the nature and work of living organisms. Materials. — Specimens of any ordinary flowering plant, such as a buttercup or butter and eggs (linaria). Somewhat similar greenhouse plants may also be used, as a geranium or primula. Living insects, as locusts. 28 THE NATURE AND NEEDS OF LIVING MATTER a. General Study of a Plant Observations. — 1. Find four different parts to the plant. What are they ? 2. What is the greatest difference between root and stem? Can you find joints in the roots ? 3. Are the leaves arranged on the stem in a regular or irregular fashion? 4. Do you find any parts of the flower that appear like modified (changed) leaves ? 5. How many circles of parts can be found in the flower ? How many parts in a circle ? Conclusions. — 1. What do you think is one of the purposes (functions) of roots ? Reasons ? 2. What is one of the evident functions of the stem ? 3. How are the leaves arranged so as to get the most sun- light ? 4. Is there any relation between parts exposed to sunlight and the green coloring matter (chlorophyll) ? Note. — Roots, stems, and leaves are known as vegetative organs, as they are necessary to the life and growth of most individual plants. 5. What is produced by the flowers of apple trees ? What is contained within the core of the apple ? Then what do you think is the function of flowers? Why are they of espe- cial importance? b. General Study of an Animal Apparatus. — Small glass jars covered with netting to serve as vivaria, or " live boxes," clover or grass, hand lens, bristles. 1. ACTIVITIES Method. — Place two or three live grasshoppers1 in a viva- rium containing some grass or clover, and observe them carefully for a few minutes. 1 A live butterfly or any other living insect will do just as well. THE NATURE AND NEEDS OF LIVING MATTER 29 Observations. — 1. Is it easy to see them in these surround- ings ? Explain. 2. Do they try to hide or conceal themselves ? 3. How does a grasshopper walk ? Which set of legs seems to be used the most in walking ? 4. With a bristle cause a grasshopper to jump. Which pair of legs is used ? 5. Can a grasshopper fly ? Conclusions. — 1. How are the jumping legs fitted (adapted) for their purpose ? 2. How is the grasshopper adapted for flying ? 3. What do you conclude is the most common mode of locomotion ? 4. Why are the posterior or hind legs so differently placed as compared with the anterior or front ones ? 2. RESPIRATION Observations. — 1. Note the movements of the abdomen. Are they regular ? 2. Look for small breathing pores (spiracles) along the sides of the abdomen. Conclusion. — Through what openings does a grasshopper breathe ? 3. FEEDING Observations. — 1. Watch grasshoppers feeding in the viva- rium. Do they hold the leaves lengthwise or crosswise of the mouth ? 2. Note the upper and lower lips. Are they movable ? 3. Find dark brown jaws, mandibles, underneath the lips. Conclusions. — 1. Which way must the jaws move to meet the food ? 2. What difficulty in eating would arise if there were no lips? 4. SENSE ORGANS Observations. — 1. Note the antennae or "horns" of the grasshopper. What different positions do they take ? 30 THE NATURE AND NEEDS OF LIVING MATTER 2. Can you find compound eyes (large) ? Any others (small) ? Conclusions. — 1. Do the different positions of the antennae seem to have any relation to the different movements or posi- tions of the grasshopper ? 2. From your study of a plant and an animal, what conclu- sions can you form concerning functions and organs ? c. A Study in Variation (Optional) 1. GENERAL STUDY Observations. — 1. Compare the plant you are studying with another of the same sort. Are they the same height ? Color? 2. How do the leaves differ in shape ? Number ? 3. How do the stems differ in size ? Color ? Veining ? Hairiness ? Shape of margins, etc., etc. ? 4. How do the flowers differ? Conclusions. — 1. Are plants of the same sort exactly alike ? 2. Are any two persons exactly alike ? 3. What do you conclude regarding differences between individual plants or animals ? 2. GRAPHIC REPRESENTATION Observations. — 1. Count the number of rays in a large quantity of any wild autumn flower, such as the ox-eye daisy or an aster. If such plants cannot be had, use any other wild plant and make the leaves or stems the basis of study. 2. Suppose the number of rays varies from six to thirty. Sort the plants into piles, putting all with six rays into the first pile, all with seven rays into the second pile, and so on. Which pile is the largest ? 3. Let the small squares on the vertical lines of a sheet of cross section paper represent the number of flowers, or leaves, etc., in any par- ticular pile, and number them with the number of rays noted. Choose every other line (to prevent crowding), and count up on the lines the number of squares that represent the number of flowers with the number of rays indicated, and make a small check. Thus in Figure 6, one flower was 6-rayed, 10 flowers were 14-rayed, 29 were 20-rayed, etc. Now connect all the checks with a curved line, and we get what might be called the "curve of variation" for the particular kind of ox-eye daisy studied. Note. — These variations are of the ordinary sort and may be called THE NATURE AND NEEDS OF LIVING MATTER 31 fluctuating variations, to distinguish them from sudden variations or sports. f • Conclusions. — 1. What sort of a rayed blossom does the above kind of plant tend to produce ? Note. — If the curve you get tends to be double, it would indicate a splitting up of the sort into two other sorts with rays predominating as indicated by the two longest lines, respectively. b 20 10 14 o 17 lfl 19 .20 21 Zi 23 & 25 <"> *T Z*t £9 *9 & a c FIG. 6. — Curve of variation in number of petals of ox-eye daisy. Number of plants examined on line ab. Number of petals to a flower on line ac. 2. What tendencies of flower, or leaf, buds, stems, etc. , are indicated by your figure ? Note. — Whoever wishes to improve plants must be on the alert to notice desirable variations and attempt to propagate them. Questions 1. What are the four essential parts of a flowering plant? 2. How are flowers of advantage to the plant that bears them ? 3. What do you think Tennyson meant by the following statement ? " but if I could understand What you are, root and all, and all in all, I should know what God and Man is." 4. What do you understand by the phrase "adaptation of structure to function " ? 5. What is meant by ' variation » in organisms ? 6. What use may man make of variation ? 32 THE NATURE AND NEEDS OF LIVING MATTER References Hunter, Essentials of Biology. Chap. III. Hunter, Elements of Biology. Chap. III. Bailey, Plant Breeding. Lecture I. Osterhout, Experiments with Plants. Chap. X. EXERCISE (Optional) 1 A study of the construction and use of the compound microscope. THE MICROSCOPE 1. Note. — The microscope, an instrument for making small objects appear larger, comprises two parts : the stand and the lenses. 2. Note. — The stand consists of the following parts: foot or base, pillar, arm, tube, diaphragm, mirror, revolving nose piece, the coarse adjustment, and the fine adjustment. a. Describe the location of the perforation in the stage. 6. What is its use ? w c. What is the use of the revolving wheel, or diaphragm, pivoted to the stage ? 3. Note. — Below the stage is a movable bar carrying the mirrors or reflectors. a. In how many different directions can you move the mirrors ? 6. What is the advantage of having them movable ? c. What is the use of the mirrors ? 4. Note. — A hollow cylinder containing two lenses fits into the upper end of the tube. It is called the eyepiece or ocular. a. Why is the name ' eyepiece ' applied ? 5. Note. — Small brass cases, each containing several lenses, are at- tached to the tube at its lower end : they are the object lenses or objectives. a. Why is the name ' objective ' given to these lenses ? 6. How many objectives are there in your microscope ? 6. Note. — The low power (a slightly magnifying objective) has a short and broad case. The high power objective has a long and nar- row case. 1 Adapted from Hunter and Valentine, Laboratory Manual. Henry Holt and Company. THE NATURE AND NEEDS OF LIVING MATTER 33 M FIG. 7. — Compound microscope. B, pillar; D, tube or body; F, objective; G, eyepiece; H, draw tube; J, coarse adjustment; K, milled wheel; L, fine adjustment ; M, stage ; O, mirror ; S, diaphragm. SHARPE 8 LAB. MAN. 34 THE NATURE AND NEEDS OF LIVING MATTER a. What fractional numbers do you find on the case of the high and the low power objectives, respectively ? 7. Note. — The objectives are attached to a revolving device, the nose piece. a. What are the advantages of a revolving nose piece ? 8. Note. — To obtain a clear image of the object under examination, we must be able to vary the distance between the lenses and the object ; that is, to focus the instrument. The microscope is brought into focus by slightly turning either of the large wheels placed at the top of the arm near the tube. . a. Why are these wheels called the coarse adjustment ? (Turn one of them gently.) 6. What movement results ? 9. Note. — The milled head of the fine adjustment is found at the top of the pillar. a. Carefully turn the 'fine adjustment back and forth. ( No more than half a turn in either direction.} Why is this adjustment called ' fine ' ? CAUTIONS AND HINTS 1. Do not touch either lenses or mirrors. 2. Do not rest either your arm or your head on the instrument. 3. Never make more than half a turn either way with the fine adjust- ment. 4. Get a fairly clear image with the coarse adjustment : use the fine adjustment only to complete the operation of focusing. 5. An object to be viewed with the compound microscope should be very thin and transparent. PRELIMINARY PRACTICE WITH THE MICROSCOPE Materials. — Slides, cover glasses, free-hand sections of potato tuber stained with iodine solution, compound microscope. Directions for Mounting Sections and Adjusting Microscopes. — 1. Place the given section on a slide in a drop of water. 2. Clean a cover glass and lower it gently over the object. (Avoid air bubbles !) 3. Put the slide on the stage with the object over the stage perforation. 4. Tilt the mirror so that the object may be well lighted. 5. By aid of the coarse adjustment, bring the low power near to the object. 6. With your eye at the ocular, raise the tube from the stage till the image appears rather clearly. THE NATURE AND NEEDS OF LIVING MATTER 35 7. Make the image entirely clear by a slight turn of the fine adjust- ment to one side or the other. a. Study of Cells and Starch Grains Direction. — Study the cellulose walls inclosing spaces in which lie the deeply stained starch grains. 1. What color does cellulose show under the microscope ? 2. What color is shown by starch grains treated with iodine ? b. Study of a Drop of Milk (an Emulsion) 1. Place drop of milk on slide. Cover with slip. Notice the small globules of fat floating in a liquid. Are all these of the same size ? ' 2. Are they equally abundant in all parts of the field ? Note. — A liquid containing large numbers of tiny fat droplets is called an emulsion. 3. Shake some olive oil and water together in a test tube. What is the color ? Appearance ? PROBLEM V The structure and general properties of living matter. a. General Structure 1. SINGLE CELLS Method. — Scrape off some of the green " dust " so commonly seen on the north sides of trees and allow it to stand in water for a day or two. • Mount some in a little water and study with the compound microscope,1 first using low power, then high power. (2 Dem.) Optionally use any one-celled alga, as desmids. Observations. — 1. What is the color of a single plant (cell)? Form ? 2. Are the cells alike? If not, what differences ? 3. Do you find any cells splitting into two or four parts ? 1 Much may be accomplished by setting one microscope so that pupils may see the demonstration in turn while the rest are studying charts, references, etc., or making sketches, at the discretion of the teacher. 2 Dem. indicates a demonstration by the instructor. Here introduce a short 3tudy of the use of the microscope. See Exercise, page 32. 36 THE NATURE AND NEEDS OF LIVING MATTER 4. Note. — The outer covering of a cell is known as a cell wall, its contents is the living matter of the cell, or protoplasm. The green coloring matter is chlorophyll. The protoplasm is further separated into a small darker lens-shaped body, the nucleus, and a surrounding portion, the cytoplasm. Try finding cell wall, nucleus, and chlorophyll in your specimen. Also in Figure 8. 5. Dem. — Show any single-celled animal of a hay infusion. What are the most evi- dent differences between these cells and the plant cells ? Conclusions. — 1. Are the individual plants one-celled or many-celled ? 2. How does this plant form new plants or reproduce ? 3. How distinguish plant cells from animal cells ? Note. — Some special cases are difficult to decide, but do not concern us now. 4. What is a cell ? 2. TISSUES AND ORGANS Method. — Scrape some cells from the inside lining of the cheek with a sterilized knife. Mount in water. Stain with methyl green. The outer skin of a frog and onion skin may also be used in the same manner. Observations. — 1. Look for cell walls, nuclei, etc. 2. What is the shape of a single cell ? 3. Are the cells evidently free, or mostly united with one another ? FIG. 8. — Parts of a cell, and stages in the division of a cell to form two cells. THE NATURE AND NEEDS OF LIVING MATTER 37 Note. — Where cells are united, whether in plant or animal structure, they are said to form tissues. Thus there is nerve tissue, muscle tissue, etc., in animals, and there are many other tissues in Dlants. FIG. 9.— Drawings of sections of cells. Showing some various sorts much magnified. 6, bone cell; c, epithelium cell from the intestine; e, flat epithelium cell from the mouth ; /, fat cell ; n, nerve cell from the brain ; m, muscle cell. 4. (Optional.) — Sketch a few of the cells stained with methyl green, especially showing cell walls, nuclei, and relations to one another. Conclusions. — 1. Distinguish between one-celled and many- celled plants or animals. 2. In what ways are plant and animal cells alike ? How unlike ? 3. What are tissues ? WThat is the unit of their structure ? Note. — Tissues are grouped in both plants and animals to form organs, — as a leaf, a root, the hand, the eye, etc. b. Simple Properties Note to Teacher. — Spirogyra, or pond scum, stamen hairs of spiderwort (tradescantia), leaves of nitella, vallisneria, elodea, or the root hairs of almost any aquatic plant are good for this exercise. Unless time is no object, it is likely better simply to set up a few microscopes with any of the above 38 THE NATURE AND NEEDS OF LIVING MATTER preparations under high power, and permit the pupils, one at a time, to briefly note the protoplasmic movements. Since elodea is quite common in ponds and streams, and is so easily kept on hand in aquaria, it is recommended as best for the present purposes. Observations. — 1. Examine a bit of mounted living leaf of elodea or other selected study! What is the general color ? Can you see cell walls ? 2. Are the cells single, or joined in a tissue ? 3. Look closely for any indications of movements in the cell — moving protoplasm. What is its appearance? 4. Does the protoplasm (cytoplasm) move in any special ways with reference to the nucleus ? Conclusions. — 1. In what part of plants may protoplasm be found ? 2. Write a paragraph, telling of the appearance, movements, etc., of protoplasm. Questions 1. What is a cell ? Tissue ? Organ ? 2. What is an organism ? Give reasons for your answer. 3. What is protoplasm ? Cytoplasm? Nucleus? 4. What is the unit of structure of living things ? 5. What are some of the properties of living things ? 6. How may cells reproduce ? 7. What do you suppose is meant by the statement "one touch of nature makes the whole world kin " ? 8. Why is it necessary that there should be differences of function among the cells of a body ? 9. Why could not a cell in the body provide for its own wants ? 10. What happens to a body if part of the cells fail in their work? 11. Mention some points in which the body reminds you of a community of people. 12. What are some of the needs of a cell ? THE NATURE AND NEEDS OF LIVING MATTER 39 Special Reports 1. The cell theory of Schleiden and Schwann. (See Foot-Notes to Evolution.} 2. Protoplasm and its properties. 3. The human body or a plant- as a colony of cells. References Hunter, Essentials of Biology. Chap. III. Hunter, Elements of Biology. Chap. III. Jordan, Foot-Notes to Evolution, pp. 147-148. Thompson, Animal Life. Chap. XI. Davison, The Human Body and Health (Advanced). Chap. II. Ritchie, Human Physiology. Chap. I. To express a thought in one's own language is worth ten times more for mind growth than to state it in words learned from the book. — DAVI- PHYSIOLOGICAL PROCESSES AND RELATIONS IN PLANTS PROBLEM VI The structure and work of the parts of a simple flower. Materials. — Any simple flower, such as the buttercup, sedum, etc., hand lens, compound microscope, sugar solution. a. The Flower Observations. — 1. Find green leaflike parts (sepals). How many are there ? 2. Are they separate or united? Note. — The sepals taken together constitute the calyx. Conclusion. — What do you conclude is their use or function ? Observation. — How many colored parts (petals) are there ? Note. — The petals taken together form the corolla. Conclusion. — Can you think of any functions of the corolla ? Observations. — 1. Observe a number of slender stalks (fila- ments), with dusty knobbed ends (anthers), which taken to- gether are called stamens. How many stamens are there ? 2. Find just how the anthers are joined to the filament. 3. What is the color of the anthers ? Appearance ? 4. Can you find dustlike material (pollen) on and in the anthers ? 5. Can you find places in the anthers through which the pollen has escaped ? 6. Find some podlike structures (pistils or carpels), located in the center of the blossom. How many are there ? 40 PHYSIOLOGICAL PROCESSES IN PLANTS 41 7. Note the broad base (ovary) of a pistil. Also find a more or less stalklike portion (style) which, terminates in a rough- ened sticky tip (stigma). Note. — The stigma usually has upon it a sweet, sticky substance in which pollen grains may grow much as a seed would sprout. Conclusion. — Do the stamens and pistils have the same or different functions? Keasons for your answer? Drawings. — 1. A flower from above. Label all parts. 2. A stamen, showing all parts. 3. A pistil, showing all parts. Observations (Home Work}. — 1. Locate some flower buds. Care- fully remove the calyx from one of them. After a time compare in de- velopment with other buds. Result ? 2. Remove the corolla from another bud. -Do insects visit it ? 3. Remove the stigma from another young blossom. Effect on fruit after a few weeks ? 4. Cover a cluster of flower buds with a paper bag. Effect on fruit in a few weeks ? Conclusion. — Name a function of the calyx ; corolla ; stigma ; pollen (as decided by experiment). b. Pollen Method. — Dust-some buttercup pollen on a piece of paper, or a glass slide. Examine it with a hand lens. Make a solution of about 20 grams of sugar with about 80 grams of water. Make another solution about one half as strong. Place some of each solution in watch glasses, and dust some ripe pollen in each. Place them under a small bell jar with a moist sponge, and examine them from time to time with the low power of a compound microscope. Also try tulip or narcissus pollen in 3% cane sugar solution, sweet pea or nasturtium pollen in 15% cane sugar solution. Note. — Some prefer to make a "hanging drop" preparation by placing a drop of the solution used with some pollen on a cover glass and inverting it on a small ring which has been placed on an ordinary slide. Seal it with vaseline, and watch for sprouting pollen. 42 PHYSIOLOGICAL PROCESSES IN PLANTS Observation. — Find any sproutlike tubes (pollen tubes) ex- tending from the pollen grains. Describe them, or sketch a few. Conclusions. — 1. Are the stigmas in a blossom in such a position that pollen might commonly reach them ? Explain. 2. The sugar solution served as food for the growth of the pollen tube. Can you see any reason for there being a similar solution on the stigma? Note. — The pollen tube is long and threadlike, and carries in its growing end a very important structure (sperm cell). (See Figures and Charts for further explanation.) c. The Pistil Materials. — Pistils of such flowers as lily or tulip, some cut lengthwise and some cut crosswise. Chart or text Figures. Observations. — 1. Find a number of rounded bodies (ovules') in the ovary. Describe one. 2. Are the ovules few or abundant ? Note. — The ovules become seeds if the sperm cell in the tip of the pollen sprout ever succeeds in reaching a somewhat similar cell (egg) located in the ovule. The pollen grain sprouts in the sweet food on the stigma, and sends' the sprout down through the style until finally the two cells — the sperm cell and the egg cell — unite to form a single cell. See Figure 85. The egg is now said to be fertilized, and the process is known as fertilization. The fertilized egg now develops a minute struc- ture called the embryo, and the ovule is now a seed. The embryo of the seed will develop into the future plant when the conditions needed are present. We now see that only pollen and eggs are necessary for the formation of seeds, — so the anthers and pistils are known as the necessary or essential organs. PHYSIOLOGICAL PROCESSES IN PLANTS 43 PROBLEM VII A study of cross-pollination and some of the means of bringing it about. a. Adaptations in the Flower Method. — Study the structure of a butter and eggs or similar blossom, looking for any adaptations or fitness for cross-polli- nation or fertilization. Observations. — 1. Are the sepals of the same size and shape, i.e. regular? . 2. How do the petals and sepals compare in number ? In size and shape? Might the pollen that finally reaches the stigma more* likely come from the same flower (Self-fertiliza- tion) or from a different flower (Cross-fertilization or polli- nation) ? 3. See if you can make out the landing place of a bee should it visit this flower for nectar or honey. 4. Find the anthers and stigma. Can the pollen readily reach the stigma without some outside aid ? Conclusion. — Show how such a peculiar form of corolla fits it more especially for the visits of bees. b. Adaptations in an Insect Agent Method. — Study dried or alcoholic specimens of the bumble- bee or honeybee. Note to the Teacher. — In place of using the following questions it may be well to try permitting the pupils to ask and answer their own questions. In fact, this should be done wherever it seems feasible. Observations. — 1. How many distinct regions has the body ? Note. — These regions are known as the head, thorax, and abdomen, in order. 2. How many pairs of wings do you find ? Of legs ? To what part of the body are they fastened ? 44 PHYSIOLOGICAL PROCESSES IN PLANTS 3. Do you find mouth parts fitted for biting (jaws), or for sucking, or both ? 4. Are the legs segmented (jointed) ? What structures do you find on the feet? 5. Are the legs smooth or hairy ? If hairy, which segment is the most so? Conclusions. — 1. What do you think is the purpose of joints in the legs ? What would be the result if there were no joints? 2. What do you think is the purpose of hooks on the feet? 3. Could the hairy legs hold pollen ? Which segment could carry the most, if any ? 4. How do you think an insect may be an aid in cross-fer- tilizing flowers ? 5. How does a flower serve the bee ? How, in turn, does the bee serve the flower ? c. Field Work (Optional)1 1. GENERAL WORK Observations. — 1. Visit a locality where flowers are abundant. Are they being visited by insects ? 2. Can you tell what sort of insects ? Are they few or abundant ? 3. Do bees visit flowers of one sort in succession, or of different sorts? 4. If butterflies are present, try to determine as for the bees. 5. Describe any peculiarities of the flowers visited by the bees, such as irregularity, strong perfume, nectar, etc. Conclusions. — 1. Write out a report of your observations in a note- book. Bring it to class conference for discussion. 2. What is evidently the purpose of irregular flowers ? Of nectar ? Of perfume ? i It would also be interesting to see if any flowers prevent pollinating their own pistils, or if there are any devices for preventing the visits of unsuitable insects. PHYSIOLOGICAL PROCESSES IN PLANTS 45 2. SPECIAL DIRECTIONS FOR THE STUDY OF SOME FALL FLOWERS.1 Field Flowers. — Let us now take up some common wild flowers easily found in the fall of the year, and work out the relation of the parts of the flower to its insect visitors. Remember that the important part of these exercises is to find how and by what means the flower is adapted or fitted to receive the visits of insects. This work can be done best on field trips, but it can readily be modified so as to be useful as a schoolroom ex- ercise. The Evening Primrose ( Onagra biennis~) . — The habitat preferred by this flower is dry fields, roadsides, or waste places. The yellow flowers are found in long, upright, densely crowded clusters. A flower cluster in which the individual flowers have no flower stalks or pedicles, with one main axis to the cluster, is called a spike. Notice that young and old flowers and fruits are all on the same cluster. Where are the youngest flowers located in the cluster? Is there any flower at the end of the main stalk ? Could you determine in advance the length of the flower cluster ? Such a cluster is said to be indeterminate. Why ? Study a single open flower. Note the calyx and corolla ; are the parts distinct ? How many petals do you find ? Notice that there are eight stamens and that the stigma is four-parted. Cut the ovary in cross section, and see how many locules (spaces) there are. When a flower has each circle of parts, as the sepals, petals, stamens, and pistils, made up of a certain number of divisions, or when they appear in multiples of that number, the flower is said to be symmetrical. Here we see a very striking example of symmetry in a flower. The chief attraction to insects is the nectar, which is formed in nectar glands at tl.e base inside the slender tubular corolla. Information is given to the insects of the contents by a faint, sweet odor. This flower is not visited by many day-flying insects. Can you determine the names of any that do come by day? At night the flower opens more widely and the scent becomes much more noticeable. Moths are its chief night visitors. The long proboscis is thrust into the flower and quickly withdrawn, but usually a little pollen is carried off on the palps (projections on the sides of the head). This maybe left on the next flower visited. Try to determine what other insects, if any, visit the evening primrose at night. Draw a single flower split open lengthwise to show the position of the parts, and especially any adaptations to insect pollination. Look for any special means for the prevention of self-pollination. Label all the parts. Moth Mullein (Verbascum Uatiaria}. — The moth mullein is one of the most beautiful weeds, despite the fact that few blossoms are found at any given time. The plant flourishes on dry, waste land, roadsides, and open fields. It was introduced into this country and has since become common here and in Canada. The flowers are found in a long, loose raceme. A raceme is like a spike, except that each flower has its own flower stalk developed. Has 1 Adapted from Hunter, Elements of Biology. 46 PHYSIOLOGICAL PROCESSES IN PLANTS this cluster yellow or white flowers? Into how many parts is the calyx divided ? The corolla ? Is the corolla perfectly regular ? Notice the live stamens ; is there anything peculiar about the filaments ? Are they all of the same length ? In spite of the fact that the flower is called moth mullein, it is not pollinated to any extent by moths. Bees and flies are the chief pollen bearers. Bees which alight on this flower do so for the purpose of collecting pollen. . This they usually gather from the short stamens while they cling to the longer ones. As the bee lights on another flower, the pollen on the under side of the body is transferred to the stigma of this flower. Draw the flower from above, twice natural size. Jewel Weed (Impatiens 6(#ora).— One of the most prevalent of all our brookside flowers is the jewel weed. It well deserves its name, a pendent flaming jewel of orange. The flower is very irregular in shape. Are the flowers single or in clusters ? The sepals as well as the petals are colored. The former are three in number, one of which is saclike in shape and contracted at one end into a spur. The petals are also three in number. Open the flower. Notice how short the filaments of the five stamens are. Make a note of their position with relation to the pistil. Would self-pollination be possible in this flower ? If it is possible to study jewel weed out of doors in its native habitat, it will be found that humming birds are the visitors which seem best adapted to cross-pollinate the flower. A careful series of observations by some girl or boy upon the cross-pollination of this flower might add much to our knowledge regarding it. Jewel weed has the habit of producing (usually in the fall) incon- spicuous flowers which never open but which produce seeds capable of germination and growth. Such flowers are said to be cleistogamous. In England, where the plant has been introduced, it is found to produce more cleistogamous flowers than showy ones, and the showy ones do not produce seed. There are no humming birds in England, and without this means of pollination, the cleistogamous form prevails. Make a front view drawing of the flower of jewel weed twice natural size. d. Other Agents Method. — Refer to or study as many other flowers as possible. Study the Figures of other types, using charts or texts. Observations. — 1 . Seek for any peculiarities of structure that would lead you to think that they are for purposes of pollination. If possible, especially study the structure of the sage blossom, pea or bean, and violet. 2. Find out how pollination is accomplished in the corn plant and the willow. 3. Find out the same thing for pines. Eel grass. Primrose. Jack in the pulpit. Iris. Orchids. PHYSIOLOGICAL PROCESSES IN PLANTS 47 Conclusion. — In what other ways do you find pollination may be brought about ? Tabulate your results as follows : — AGENTS OF POLLINATIOX EXAMPLES Insects . ... Wind . ' Y Water . ..... Other agents . ... - :v "• ' Questions 1. How is a sage blossom fitted for the visits of insects ? 2. Do all flowers of an apple tree produce seeds ? How do you know ? 3. Why do flowers produce an abundance of pollen ? 4. Why does a "volunteer" stalk of corn standing alone in a garden commonly have but a few grains of corn on the ear ? 5. Do insects intentionally carry pollen ? 6. Why do bees visit flowers ? 7. Does the odor of flowers seem of any consequence ? Nec- tar ? 8. What is the importance of color in flowers ? 9. Have you ever seen insects moving from flower to flower ? What do you infer ? 10. Show why bees are likely to visit flowers before the pol- len is ripe, or the stigma ready to receive it. 11. Do you infer that bees are able to see, smell, and taste ? 12. What other insects have you ever seen visit flowers ? 13. Could a solitary willow bear seeds ? 14. What determines the position of the flower and fruit ? 15. What animals other than insects act as fertilizing agents ? 16. Night-opening flowers are commonly white, sweet-smell- ing, and large. Is this of any advantage ? 48 PHYSIOLOGICAL PROCESSES IN PLANTS 17. Do any flowers have arrangements for protection against undesirable visitors ? 18. What are the essential organs of a flower? Why so called ? 19. What is artificial pollination ? What is its importance to man ? 20. What do you think Bryant meant when he wrote : — To him who in the love of Nature holds Communion with her visible forms, she speaks A various language ; — 21. Do flowers cross-fertilized by the wind have gayly col- ored corollas ? Odor ? Nectar ? Explain. References Hunter, Essentials of Biology. Chap. IV. Osterhout, Experiments with Plants. Chap. VL Miiller, Fertilization of Flowers. Weed, Ten New England Blossoms. ^ Gibson, Sharp Eyes and My Studio Neighbors. Darwin, Cross- and Self-fertilization^ etc. Ely, "Color Arrangement of Flowers." Scribner's Magazine, March, 1910. Dana, Plants and their Children. Dana, How to Know the Wild Flowers. Stack, Wild Flowers Every Child Should Know. Gibson, W. H., "The Milkweed," in My Studio Neighbors, p. 227. PROBLEM VIII1 A study of fruits. Note. — A fruit is here defined as a ripe or ripening ovary or seed case, with its contents and any attached parts. Materials. — Pea pods or bean pods, apples, etc. 1 The seed experiments for Problems X-XIV should be started now. PHYSIOLOGICAL PROCESSES IN PLANTS 49 a. Uses to the Plant 1. PEAS OR BEANS. (Legumes.) Observations. — 1. Examine an unopened pod. Can you find the ovary or seed case ? Style and stigma ? 2. Open a pod and see if you can verify the above. 3. Note that the ovules are not all the same size. Conclusions. — 1. Can you explain why the ovules are not all the same size ? 2. Can you think of at least one function (use) of a fruit ? 3. Sketch a half pod, with the contained ovules. Label all parts. 2. APPLE. (A pome.) (Optional.) Materials. — Preserved or fresh apple blossoms in various stages. Apples. Observations. — 1. Find the calyx in an apple blossom. Are the sepals separated at the base or united ? Thin or thick ? 2. What part of the blossom seems most likely to develop into the fruit? 3. Do you find any indications of the calyx remaining on an apple ? Conclusions. — From what does the fleshy part of an apple develop ? Give some reasons for your answer. Observations. — 1. Remove the skin from an apple and leave the pared apple exposed to the air for a few hours. What results? (Weigh the apple both before and after the experiment.) 2. Break the skin of an apple and set the apple aside for a few days. Note what results. Conclusions. — 1. What are some of the functions of the skin of fruits ? 2. Cut cross and longitudinal sections of an apple. Can you find the seed cases (locules) of the ovary ? How many are there ? What seems to be their function ? b. Means of Scattering Fruits and Seeds Materials. — Fruits of linden, burdock, oxalis, clotbur, thistle, beggar's tick, violet, maple, tumbleweed, dandelion, coconut, crane's bill, cherry, raspberry, acorn, nuts, peach, chestnut, pines, pea, peanut, jimson weed, green berries, etc. SHARPE'S LAB. MAN. — 4 50 PHYSIOLOGICAL PROCESSES IN PLANTS Observation. — Study as many of the above fruits as may be available, and classify under the following table, giving means of dispersal. EXPLOSIVE WIND- CARRIED BURS, ETC., ON. FURRY COATS, ETC. SQUIRRELS BIRDS MAN OTHER MEANS Conclusion. — 1. Write a paragraph on the different ways seeds may be dispersed, and give an example of each. c. Protection from Animals (Optional) Observation. — Examine as many specimens of the fruits provided as possible, and see if you can tell just how they protect themselves from being destroyed by animals. Tabulate your results under the following headings : — BITTER OR SOUR TASTE WHILE YOUNG HARD COVERING SPINES SUSPENSION ON SLENDER STALKS CONCEALED UNDER GROUND OTHER MEANS Conclusion. — How may fruits protect themselves from animals ? Give examples. r PHYSIOLOGICAL PROCESSES IN PLANTS 51 d. Field Work Observations. — 1. Visit a vacant lot, a city park, or country fields, and collect as many examples of fruits scattering their seeds as you can. Get the common names of those you do not know from your instructor. Label some boxes, using the head- ings of the two preceding exercises, and sort the material in the proper boxes. Give them to the school museum, if you so desire. 2. Take as many notes as you can concerning any observa- tions you may make in the field. Note especially the means of protection and distribution, even though you may not know the name of the fruit until told. Questions 1. Why do most plants produce a large number of seeds ? 2. What advantage to plants that their seeds be widely dis- tributed ? 3. Are cotton fibers on the fruit or on the seed ? 4. Visit some vacant lot and observe how the common weed seeds there are scattered. 5. What is the purpose of fleshy fruits ? 6. Is an ear of corn a fruit, or a collection of fruits ? 7. What is the purpose of the husk of corn ? 8. What is the purpose of the bright colors and sweet tastes of fruits ? 9. How might coral islands far at sea become supplied with various seeds ? 10. How might the seeds of undesirable plants be brought to this country ? 11. How might railroads affect seed dispersal ? 12. Should a weedy vacant lot be burned over in the fall or in the spring ? Explain. 13. Describe the process by which plants produce fruits. 14. What is the chief use of fruits to plants ? 52 PHYSIOLOGICAL PROCESSES IN PLANTS Special Reports 1. The work of Luther Burbank. 2. The spread of the Russian thistle. 3. The spread of the wild lettuce. 4. Weeds that have been imported, and how they were brought here. 5. The struggle of plants for existence. 6. The economic value of fruits. 7. The part taken by Indian corn in the development of America. 8. The wheat crop as an index to a country's prosperity. 9- The various uses of fruits. 10. Boards of Trade and their work. 11. Cotton and its part in the development of the United States. References Hunter, Essentials of Biology. Chap. V. Osterhout, Experiments with Plants. Chap. VII. Hodge, Nature Study and Life. Rusby, "Wild Foods of November." Country Life in America, November, 1900. - "Wild Foods of the U. S. for September." Country Life in America, October, 1906. Dickson, Harris, "Dethroning King Cotton." Saturday Evening Post, July 2, 1910. Beal, Seed Dispersal. Walton, Practical Guide to the Wild Flowers and Fruits. Boynton, "Seeds Stealing a Ride." Nature Study Leaflet,~No. 4, October, 1909. Cornell Univ. "Seed Dispersal," Home Nature Study Course, Cornell Univ., No. 1, October, 1904. Thompson, " F, merge ncy Foods in the Northern Forest." Country Life in America, September, 1904, p. 438. PROBLEM IX The economic valvue of some fruits*- Method. — Collect as many different kinds of fruits as possible, orchard fruits, garden fruits, etc., as berries, beans, pumpkin, 1 The pupils should be encouraged to bring pertinent newspaper or maga- zine articles to class. These may be pasted in a proper notebook and indexed. It is also wise to catalogue all the better articles. PHYSIOLOGICAL PROCESSES IN PLANTS 53 tomato, cucumber, etc., also nuts, grapes, market fruits, weed fruits, etc. Sort them into two groups — the fleshy fruits and the dry fruits. Pick out and label a sample of each sort for the school museum. Fill out the following tabulation as far as you can. (See References.) 1. USEFUL FRUITS NATIVE HOME OK HABITAT ANNUAL CASH VALUE USES TO GAUDEN FRUITS : 1. Peas v . 2. Beans . .. 3. Pumpkins . . . .1 . 4. Cucumbers . . . ^. Etc. . ORCHARD FRUITS : . 1. Apples . . . < 2. Pears . . . / 3. Peaches . . /4. Quinces . . 5. Apricots . . ^ 6. Plums . . . 7. Cherries . . Etc. . . GRAINS : -1. Wheat * 2. Rye . / 3. Corn / 4. Oats 5. Barley ^6. Rice Etc. . 54 PHYSIOLOGICAL PROCESSES IN PLANTS FRUITS NATIVE HOME OB HABITAT ANNUAL CASH USES TO MAN MISCELLANEOUS : — 1. Cotton . . . / 2. Bananas . . > 3. Coconut husk x 4. Coffee . . . 5. Cocoa . . . 6. Pepper . . . ^7. Opium . . . Etc. . 2. HARMFUL FRUITS NATIVE HOME OR HABITAT ESTIMATED Loss HOW THEY DO HARM WEEDS : \ 1. Wild lettuce . „ 2. Purslane 3. Pigweed 4. Ragweed 6. Canada thistle . / . . ^ 6. Cocklebur ....;. 7. Wild carrot . . • . . . 8. Oxeye daisy 9. Dandelion 10. Milkweed etc. Questions. — 1. What kinds of fruits can you buy in the market to-day ? What prices do they bring? 2. How many kinds of corn do you know ? 3. What part did Indian corn play in the discovery of America ? 4. What is the most important index of a country's prosper- ity ? PHYSIOLOGICAL PROCESSES IN PLANTS 55 5. Name the two best corn producing states. Wheat. Rice. 6. Name some of the uses of Indian corn. 7. What part have the cereals played in civilization ? 8. Explain the statement made by J. Ogden Armour, " The call of the farm must be made the answering cry to the wail of the hungering city.'7 References Hunter, Essentials of Biology. Chap. IV. Hunter, Elements of Biology. Chap. V. Gannett, Garrison, and Houston, Commercial Geography. Chap. IX. Huntington, A. O., "Poisonous Vagrant Weeds," House and Garden, September, 1909. PROBLEM X A study of seeds in their relation to the new plant. Materials. — Kidney or lima beans soaked in water for 24 hours, dry pods of beans, vaseline, iodine solution, nitric acid, ammonia, and demonstration microscope. INTRODUCTION Bean Pod and Bean Observations. — 1. Find the ovary, style, and stigma. How distinguish them ? 2. Open the pods, and find the seeds. Where are they fastened ? Note that each seed is fastened by a little stalk (funiculus). 3. Pull a bean from its attachment. Find a scar (liilum), showing where the funiculus was attached. Where is it lo- cated ? 4. Look for a tiny hole (micropyle), near the hilum. Conclusions. — 1. What is one of the functions of a fruit ? 2. Can you think of any function of the micropyle ? Keep in mind that it leads to the egg cell. 56 PHYSIOLOGICAL PROCESSES IN PLANTS a. Relation of Embryo to Food Supply 1. INTERNAL STRUCTURE Observations. — 1. Remove the outer coat (testa) of a soaked bean. Look for another coat under it. 2. Into how many parts (cotyledons) does the rest of the bean naturally separate ? 3. Remove one cotyledon (seed leaf) very carefully, and find some minute leaves (plumule). Where are they situated? 4. Find a rodlike part (hypocotyl). Note. — The plumule later develops into the first true leaves of the plant, while the hypocotyl develops into the root and lower stem. The embryo includes all the parts of the seed that will later develop into parts of the young plant. Name these parts. Conclusions. — 1. What do you think is the use of the seed coats ? 2. What structures suggest the stem of the developed plant ? Root ? Leaves ? 3. How has the embryo been fed and protected up to this 2. FOOD SUPPLY OF THE EMBRYO Note. — For food tests see Prob. Ill, or, see Hunter, Essen- tials of Biology, Chap. V. Observations. — 1. Crush a bit of soaked bean cotyledon, and add a few drops of iodine solution. What results ? 2. Put some of this material on a glass slide and view through the demonstration microscope. Find small oval bodies stained bluish or black with the iodine. Conclusions. — 1. What food material is in the cotyledon ? Proof ? 2. What are the oval bodies seen through the microscope ? Observations. — 1. Add nitric acid to some crushed cotyledon. What color appears ? Rinse off the acid, and add ammonia. What color ? PHYSIOLOGICAL PROCESSES IN PLANTS 57 2. Put some crushed cotyledon on a piece of paper, put it in a hot place and leave it for several hours. What results? Conclusions. — 1. What other food materials do you think are present ? Reasons ? 2. What foods then form most of the first food of the young bean plant? 3. Where is most of the nourishment for the growing bean embryo stored? 3. ANOTHER USE OF THE MICROPYLE (OPTIONAL) Method a. Observations. — 1. Cover the micropyles of a few beans with vaseline. Select as many more not covered with vaseline and weigh both lots. Leave both lots in water over night. Re- weigh. What difference in weight do you find ? What difference in appearance, if any ? Conclusions. — 1. What is one of the uses of the micropyle ? 2. What other use of the micropyle do you already know? Method b. Observations. — 1. Fill a cigar box with wet sand or sawdust. Place on the surface some corn grains or beans in rows, one third with the micropyle up, one third with the opening down, and one third flat on the soil as in Figure 10. Press them firmly into the soil so that each is just half buried. Which sprout first ? Conclusions. — 1. Where may the water enter seeds ? 2. Does the seed's natural position in the soil usually bring the opening in contact with the earth ? Explain. b. How the Young Plant Makes Use of the Food Supply 1. DIGESTION Observations. — 1. Cut lengthwise through the embryo of a number of corn grains that have just begun to germinate. Place them in a test tube and test for grape sugar. (Look for FIG. 10. — Seeds half submerged in wet sand or sawdust, to determine how the water enters. (After Osterhout.) 58 PHYSIOLOGICAL PROCESSES IN PLANTS slight changes in color about the margins of the embryo.) Result ? 2. Chew some cracker slowly. Is there any change of taste? Note. — When starch is changed to grape sugar by a sub- stance found in plants or animals, the starch is said to be digested. In plants this may be accomplished by a digestive ferment, or enzyme, called diastase ; in the mouth, by a ferment in saliva (ptyalin). Method. — Add about 1 gram of diastase powder (commercial) to the same amount of starch and dilute with about 100 times as much water. Set aside in such a place that it will remain at about blood heat. Test for starch at the end of 24 hours. Result? Likewise test for grape sugar. Result? Note. — A substance is soluble if, when it is put in water, it entirely disappears from view, just as sugar or salt when placed in hot water. Conclusions. — 1. How do you conclude insoluble starch of plants may be changed into a form which is soluble ? 2. Of what benefit is it to a plant that its food matter be stored in an insoluble form? 3. Which sort of food material might more readily circulate about in a plant, starch, or sugar? Explain. 4. Wliy is it necessary, then, that plants as well as animals digest starchy and other foods ? 5. What evidently happens when you chew a cracker slowly in the mouth ? Questions 1. Why are beans of value as food for man ? 2. What other seeds can you name that are used as food for man? 3. What products come from seeds that are of value as food for man? 4. In what condition must food material be in order to circu- late in plant or animal bodies? PHYSIOLOGICAL PROCESSES IN PLANTS References Hunter, Essentials of Biology. Chap. VI. Hunter, Elements of Biology. Chap. VI. PROBLEM XI A study of the conditions ( factors} necessary for awaken- ing (germinating} the embryo in the seed. I. FACTORS a. Moisture Method. — Place a layer of moist blotting paper in each of three cups. Put six soaked beans in each. Keep the seeds in one cup about half covered with water, keep those in the second just moistened, and keep those in the third dry. Keep the cups lightly covered, and put in a moderately warm place. Examine them daily for a week or so. Observations. — Tabulate results as follows : — NUMBER OF BEANS SPROUTED DAY DRY MOIST WET First etc. , to seven days. Conclusion. — What amount of water do you think is best for germination ? Eeasons ? b. Temperature Method. — Plant equal numbers of soaked peas and beans in each of three germinating boxes or flower pots. Put one box in a warm place, where the temperature is above 80° F., another where the temperature is from 65 to 70° F., and the third where the temperature is at least below 40° F. See that all have tne same conditions of air, light, and moisture. Observe them for a week or two. 60 PHYSIOLOGICAL PROCESSES IN PLANTS Observations. — 1. Tabulate the daily observations as fol- lows : — TEMPERATI KE 1ST ,„ 86 4-ni 5TII GTH TTII STII 80 degrees and more . 65-70 degrees 30-40 degrees Conclusion. — What sort of temperature is best for germi- nating seeds ? Reasons ? c. Oxygen Method. — Fill a wide-mouthed bottle nearly full of moist sand. Put twenty soaked peas in. this bottle, and seal it air- tight. Put as many soaked peas in a similar bottle, but leave uncorked. Observe results for a week. Observations. — 1. Tabulate the daily observations as fol- lows : — NUMBEK OF PEAS SPROUTED 1ST 2i> 8n 4-rn fmi 6rir TTII Sealed bottle . . ,. Open bottle . . . . Conclusions. — 1. Do sprouting seeds need oxygen ? Rea- sons for your answer. 2. What element have you learned is in the air ? 3. What happens when oxygen combines with any other substance, as carbon or food ? 4. Do germinating seeds need food ? If so, what else do they need in order to set free the energy contained in the food ? (See Prob. I, b). 5. What is one of the main reasons farmers plow and har- row the soil ? PHYSIOLOGICAL PROCESSES IN PLANTS 61 d. Food (Some results of oxidation of food in both plants and animals.) Method. — Germinate some seeds in a small, wide-mouthed bottle. After a few days remove some of the gas above the sprouting seeds with a large bulb pipette, and bubble it through liine water. Put a lighted splint in the gas still remaining in the bottle. Observations — 1. What results when the gas was bubbled through lirnewater ? When the lighted stick was inserted ? Conclusions. — 1. WThat gas was evidently present ? Reasons for your decision ? 2. Where was this gas evidently formed ? Explain. 3. How have we heretofore learned this gas to be made ? 4. If oxidation took place in the seeds, what else should result besides giving off carbonic acid gas ? 5. Insert a thermometer among some germinating seeds, and also among a lot of seeds not germinating, but under similar conditions. Result ? 6. How do the results obtained here agree with those of your previous study of oxidation ? 7. Blow through a glass tube into some limewater. Result ? What has evidently been formed in your body ? 8. What are some of the results of oxidation of food in both plants and animals ? 9. Explain how you know seeds must breathe. References Hunter, Essentials of Biology. Chap. VI. Hunter, Elements of Bioloyy. Chap. VI. PROBLEM XII A study of young plants until they are independent (seedlings}. Material. — Soaked beans and peas. Sand or sawdust, boxes or pots. 62 PHYSIOLOGICAL PROCESSES IN PLANTS Method. — Plant the soaked seeds in pots or shallow trays, with holes in the bottom for drainage. Plant them in moist sand or sawdust. Use a box with glass side for studying root development. Keep the temperature about 72° F., and water them occasionally. Take out specimens from day to day until a complete series is obtained up to the time green leaves appear. Make sketches of these changes every other day, for about two weeks. The series of .sketches should show just what has become of each part of the embryo. a. The Bean Seedling Note. — A growing plant is called a seedling until it loses its seed leaves, or cotyledons. Observations. — 1. Which part of the embryo breaks through the seed coats first ? Where ? 2. Into what does the hypocotyl develop ? 3. What part appears first above ground ? 4. Are the cotyledons of the bean pushed or pulled out of the ground ? 5. What change takes place in the size of the cotyledons ? Color? 6. What becomes of the cotyledons in old specimens ? 7. What color has the part above ground ? Conclusion. — What does the change in size of the cotyledons indicate ? Drawing. — Draw a horizontal line across a sheet to represent the level of the sawdust or other material used. On this line make a series of 5 sketches, showing just what has become of the cotyledons, hypocotyl, and plumule. Label these parts. b. Pea Seedling (Optional) Observations. — 1. Can you find the same external structures in the pea as were found in the bean ? Name them. 2. Remove the seed coat from a soaked seed. How many cotyledons do you find ? Note. — Plants whose seeds contain two cotyledons are said to be dicotyledons. PHYSIOLOGICAL PROCESSES IN PLANTS 63 3. Find the hypocotyl and plumule. Are they located in the same place as in the bean ? 4. Watch pea seedlings develop as with the beans. Which part comes above ground first ? 5. What parts of the seedling remain be-low ground ? 6. What becomes of the cotyledons ? Conclusions. — 1 . How do the cotyledons of the pea differ in use from those of the bean ? 2. What is the principal difference between bean seedlings and pea seedlings ? Drawings. — Make a series of sketches as with the bean seedling, showing the different stages of germination and just what becomes of each part of the embryo. Fill in the following table : — PART ABOVE GROUND FIRST PARTS LEFT UNDERGROUND FATE OF THE COTYLEDONS FATE OF THE HYPOCOTYL FATE OF PLUMULE Beans . Pea . . . c. Uses of the Cotyledons Method. — Plant a few beans and peas in sawdust. After the cotyledons or leaves have appeared above the ground remove the cotyledons from half of each sort of seedling. Care for the seedlings and examine from time to time for ten days or so. What results? Conclusion. — What is at least one use of the cotyledons of the bean plant ? Of the pea ? d. The Corn Seedling (Optional) Observations. — 1. Use soaked corn grains. Find a light-colored area on one side. This marks the position of the embryo. Is it large or small compared with the entire seed ? 2. Cut a grain lengthwise through the narrow side, and find the embryo. Verify your opinion in the preceding topic as to the comparative size of the embryo. 3. Put some iodine solution on the cut surface. Kesults ? Note. — The embryo does not stain so deeply with iodine as the endo- sperm. Endosperm is food material outside the embryo. 64 PHYSIOLOGICAL PROCESSES IN PLANTS 4. Test for other food substances. Results ? Conclusion. — Is most of the food matter of corn grains inside or outside the embryo ? What foods are present ? Observations. — 1. Use a hand lens. Note that the embryo lies in such shape that the hypocotyl points toward the end that was attached, while the plumule points the other way. Note. — The tiny plumule is attached to that part of the embryo near- est the pointed end of the corn grains, which has a single cotyledon. Plants having but one cotyledon, as the corn, are known as monocotyle- dons. 2. Sketch a section as cut above x 3. Label all parts studied. Observation. — Remove the endosperm from some corn seedlings that have just germinated. Place on netting over water in a cup so that the roots reach the water. Place with them an equal number of corn seedlings with the endosperm present. Observe them for a number of days. Results ? Conclusion. — What is the use of the endosperm of corn ? PROBLEM XIII (Optional) A study of so7ne methods of plant breeding. a. Seed Selection Observations. — 1. In 1892 about 880 varieties of apples were on sale by American nurserymen. These were the result of seedlings coining up here and there by accident. If so many were produced haphazard, do you think better results might be obtained by careful selection ? 2. Sort over a number of bean seeds of any one variety. Examine numbers of ears of corn. Are they all exactly alike? If not, how do they differ ? 3. Select the seeds you think would produce the better plants. Notice weight, color, size, shape, and number of kernels to the ear. Conclusion. — Do you think it wise to carefully select seeds? Give reasons for your selection in 3. Note. — It is not sufficient to alone select what appear to be the best ears, but we must know which can transmit their good qualities in the highest degree, or find what is known as the " hereditary percentage." Before this is done, the sprouting ability of the seeds should be tested, as follows : PHYSIOLOGICAL PROCESSES IN PLANTS 65 b. Seed Testing1 1. GERMINATION Method. — Make a shallow wooden tray about l\ inches deep, 15 inches wide, and 23 inches long. Divide the tray into small spaces about 1£ inches square by a checkerboard lacing of twine across the top. Fasten the twine by tacks, and number the rows in both directions ori the sides of the tray. There should now be about 10 rows of squares the narrow way and 15 the other, as in Figure 11. Be- fore finally lacing to form the squares, loosely fill the tray with dry sand or saw- FlG 1L _ See(j testing frame. (After Howe.) dust. Soil may be used, although not so clean to handle. Arrange ears of seed corn in rows of ten to correspond with the ten rows of squares, or carefully label each ear to correspond with a certain square. Arrange the ears on shelves, where they will not be disturbed until after the test is completed. When ready to begin the test, take ear number one, and carefully re- move five kernels from each ear. (The kernels from the tips of each ear should not be used.) Take kernels of average size, removing them in a spiral manner around and lengthwise of the ear, from about one inch of the base of the ear and one inch of its tip. Plant each of these five kernels in the square which corresponds with the ear from which they were taken. Push a kernel in each of the four corners of the square point downward, and the fifth in the middle. Push all to a uniform depth, just far enough to be covered with sand when the forefinger is withdrawn. After the planting is completed, lay a small piece of paper flat on the tray and pour water on the paper until the sand is thoroughly saturated. Put the tray in a warm place and keep the sand watered until the young shoots are an inch or so high. Observation. — Examine the squares in regular order and carefully note the condition of the young seedlings. Tabulate your results, show- ing the number in a square in good condition and the number in poor condition. Conclusions. — 1. If all five plants of a square are thriving and sturdy, what is your decision concerning the ear from which these seeds came ? 2. Suppose two or more of them are shorter, or look pale and sickly. What about the chances concerning the ear from which they came ? i Adapted from Howe, Circ. 96, U. S. Dept. Agri., 1910. SHARPE'S LAB. MAN. — 5 66 PHYSIOLOGICAL PROCESSES IN PLANTS 3. Suppose there are four good plants,but the fifth is smaller, or cannot be seen at all. Dig down carefully and see if the kernel germinated, but with its tip held in place by the tough skin of the kernel. What is your conclusion ? 4. Suppose one kernel out of the five has not even sprouted, while Mie other four are an inch or so high. Conclusion ? 5. Which is more likely to cause a poor early showing in the field, — crows, cold weather, or poor seed ? 6. Show why seed corn should not be purchased already shelled. 7. Why is it unwise to use the kernels at the tip of the ears ? Give at least two reasons. Problems 1. How many hills of corn in an acre if the hills are 3 ft. 6 in. apart ? 2. How many kernels needed to plant an acre at three kernels to a hill? 3. How many kernels in an average-sized ear you are testing ? How many ears of the sort you are testing to plant an acre ? Note. — Fifteen ears of good size, at three kernels per hill, should suffice for an acre. 4. How many acres can be planted with the seed corn tested in one tray? Note. — Pupils may well test the germination of seed corn which their fathers expect to use, wherever conditions permit. If their fathers are not using seed corn, pupils may well offer to do this for neighboring farmers. The ears to be tested should be carefully numbered, five kernels taken from each by those doing the testing and arranged in small envelopes or packets, numbered to correspond with the ears. When the test is finished, send the numbers of the poor ears back to the farmer, that he may know just what ears to reject. 2. PERCENTAGE OF GERMINATION Method. — A simple seed tester may be made out of two shallow ves- sels, such as pie tins, and blotting paper or cloth. Cut the blotting paper or cloth so as to fit the bottoms of the vessels. Heat the blotters in an oven or boil the cloths in order to kill any germs that may be present. Place a blotter or cloth in the bottom of one of the shallow vessels, wet it, and place one hundred soaked radish or clover seeds upon it. Cover these with another wet blotter or cloth, and place the second vessel on the other as a cover. A glass plate may perhaps serve better as a cover. See that the rims fit well. Set aside in a good growing temperature. Observe the seeds from time to time and remove all that have germi- PHYSIOLOGICAL PROCESSES IN PLANTS 67 nated. When all have germinated that will, subtract the number remain- ing from oiiQ hundred. Note. — Suppose 20 seeds out of the 100 failed to germinate. Of course 80 germinated, or 80% of the sample. This is known as the percentage of germination. This may be calculated with 50 seeds, but the likeli- hood of error will be greater. Why? FIG. 12. — Simple seed tester. Observation. — Place 100 radish or clover seeds in a home-made tester. Remove those that germinate from time to time. How many remain ? Conclusions. — 1. What is the percentage of germination of the seeds tested ? 2. Why is it especially important that seeds, as clover, be tested for percentage of germination before planting ? Given several kinds and grades of any certain sort of seed on sale, how would you finally decide on which to buy ? Should high-priced seeds be tested before or after buying ? Note. — Very valuable aid may well be rendered neighboring farmers and gardeners by pupils in thus testing seeds which are to be used for crop raising. Peas, beans, corn, cucumbers, melons, oats, wheat, barley, etc., as well as the common garden seeds, may thus be easily tested. 3. — LARGE SEEDS VERSUS SMALL SEEDS1 Observations. — 1. Plant a few beans an inch deep in jar 1; a few clover seeds an inch deep in jar 2, the same number of clover seeds a quarter of an inch deep in jar 3. Set them aside in good growing sur- roundings, and note results daily until the seedlings are well developed. 2. Compare jars 1 and 3. Which plants develop the more vigorously? Which pushed through the greater amount of soil. Which seeds are the larger ? 1 Adapted from Goff and Mayne, First Principles of Agriculture. 68 PHYSIOLOGICAL PROCESSES IN PLANTS 3. Compare jars 2 and 3. Which plants are the most vigorous? Which pushed through the greater amount of soil ? 4. What is shown in Figure 13 ? Conclusions. — 1. How is the size of seeds related to the early seed- ling ? 2. What relation between the size of seeds and depth of planting? Explain. 123 FIG. 13. — Large versus small seeds. Jar 1, navy beans planted one inch deep; jar 2, clover seeds planted one inch deep; jar 3, clover seeds planted one quarter inch deep. 3. Give at least three reasons why farmers should reject small and shrunken kernels of corn. 4. What precautions should usually be observed in selecting seed ? c. Hereditary Percentage, or the Number of Offspring that Inherit Desired Characters Observation. — After the sprouting power of the seeds is deter- mined, the seeds from particular ears are planted in particular rows, so that the offspring of these ears can be compared. Conclusions. — 1. The poor and barren stalks are now removed be- fore the tassels appear. Why ? 2. Why should this testing lot be separated a mile or so from other fields of corn ? 3. In the autumn the best ears are now selected for next year's crop. These selections depend upon the line of improvement desired. PHYSIOLOGICAL PROCESSES IN PLANTS 69 4. Suppose an increased yield is desired. What results from culling the barren stalks ? When should they be culled ? 5. Suppose quality, such as a greater percentage of oil, is desired. Test a kernel for oil. What part contains most of the oil ? How should you select ears to develop this quality ? What does the white part of the kernel contain ? How select to develop this quality ? What is most of the rest of the kernel around the germ ? How develop this quality? 6. Suppose you wished to develop, size, shape, color, etc. How de- velop these qualities ? 7. It may be desirable to select a sort that is hardy and ripens early. The original home of corn was in Central America. How develop hardi- ness and early ripening ability ? 8. Can corn now be grown on the great alkali plains ? How might a race of corn resistant to drought be produced ? 9. A great amount of damage is annually done by corn smut. How might a resistant variety be produced ? See Hunter, Essentials of Biol- ogy, p. 81. d. Artificial Cross-pollination Observations. — 1 . Tie up a tulip or lily flower bud about ready to open with a manila bag, so that there will be no danger of foreign pollen being transferred there by bees, wind, or other foreign agents. 2. Remove the corolla and stamens en- tirely from the pistil of another tulip or lily bud of another sort, being careful to cut the stamens away before the flowers have opened, thus leaving the pistil alone on the receptacle. (Cut at the line marked "W" in Figure 14.) 3. As soon as the blossom in the bag opens, transfer some of the pollen to the stigma of the flower without stamens. This is best done by crushing a ripe anther upon the finger nail, and then transferring it to the stigma by means of a small scalpel made by hammering out the pointed end of a pin. ^ 14>_ghowi how to A camePs-hair brush may also be used. See cut away the gtamens and that the stigma is entirely covered with corona of a blossom, for pollen. Label the stigma thus pollinated, artifical cross-pollination, stating the date, from what pollinated, etc. (After Bailey.) 70 PHYSIOLOGICAL PROCESSES IN PLANTS Conclusions. — 1. If pollen is transferred from one flower to anothei flower of another variety, it is termed cross-fertilization. Why ? 2. Why cut away the anthers from one of the flowers ? Why inclose the other in a paper bag until it is ripe ? Observations. — 1. After the pod or fruit of the pollinated flower starts to grow, remove the bag. Permit the fruit to ripen. Does it differ from either of the fruits of the parent plants ? 2. Try ripening the fruits and planting the seeds, in order to deter- mine the effect of the cross-pollination. Note. — Methods simi- lar to the above are in use by Burbank and others in producing new varie- ties of fruits. Such pro- cesses are part of the work of plant breeding. e. Comparison with Animals Observations. — 1. Study Figure 15. Which of the dogs is specialized for speed? Driving cattle ? 2. Which is especially prized for stopping cattle ? Trailing by scent? Find- ing game? Drawing ve- hicles ? Going into holes ? Cold weather? House pet? 3. A hairless dog is much prized in hot cli- mates, as in Mexico, etc. Why? Conclusions. — 1. It is claimed that widely dif- fering environments under various forms of domestication cause sports. What do you think is meant by such a term ? Are they accidental or designed by man? FIG. 15. — Artificial selection among dogs. (After Romanes.) PHYSIOLOGICAL PROCESSES IN PLANTS 71 2. What advantage are these sports to breeders ? Note. — Professor De Vries has shown, by cultivating American eve- ning primroses in Europe, that such sudden changes in environment may cause not only varieties but new species to be formed. It is supposed that all varieties of dogs thus originated from the wild dog, all varieties of apples from a wild crab apple, and all varieties of pigeons from a wild pigeon, etc. Questions 1. What is a seedling ? 2. Why are the cotyledons often called " seed leaves " ? 3. What is the main use of the cotyledons of the bean ? 4. What is the use of the endosperm of corn ? 5. Give some of the methods used in plant breeding. 6. What are hybrids ? How are they commonly formed ? 7. Who is Burbank, and what has he done ? 8. What is meant by the term heredity ? 9. Explain the statement by Cornwall, " Nature ever yields reward to him who seeks and loves the best." 10. Why is plant and animal breeding of the highest importance to a nation ? 11. What is meant by the term hereditary percentage ? 12. How compute the percentage of germination of seeds ? Special Reports 1. Corn, and its use in making alcohol. 2. Barley and beer making. 3. Burbank and his work. 4. Some new plant creations. 6. Plant breeding. 6. Any newspaper or magazine articles pertinent to your studies. 7. The United States Government plant-breeding laboratory. 8. Corn culture and breeding. References Hunter, Essentials of Biology. Chap. VI. Goff and Mayne, First Principles of Agriculture. Hartley, " Injurious Effects of Premature Pollination." Bulletin 22, Plant Industry, U. S. Department of Agriculture, 1902. 72 PHYSIOLOGICAL PROCESSES IN PLANTS Bailey, Plant Breeding. Lecture III, 1904. Bailey, "Crossing of Egg Plants." Bulletin 26, Cornell Experiment Station, 14, 1891. "Effect of Pollination upon Tomatoes." Bulletin 28, Cornell Experiment Station. - " Philosophy of Crossing Plants, considered in Reference to their Improvement under Cultivation." Report of Massachusetts State Board of Agriculture, 1891. Galloway, B. T., "The Growth of Radishes as affected by the Size and Weight of the Seed." Agricultural Science, VIII, p. 557, 1894. Crosby and Howe, " School Lessons on Corn," Farmers' Bulletin 409, U. S. Department of Agriculture. Bailey, "New Ideals in the Improvement of Plants." Country Life in America, July, 1903. De Vries, Hugo, Plant Breeding. Howe, F. W., "How to Test Seed Corn in School." Circular 96, U. S. Department of Agriculture. "Boys' and Girls1 Agricultural Clubs." Farmers' Bulletin 385, U. S. Department of Agriculture, 1910. East, E. M., "The R61e of Selection in Plant Breeding." Popular Science Monthly, August. Greene, M. Louise, Among School Gardens. Charities Publishing Committee, New York City, 1910. Bailey, L. H., "A Children's Garden." Teachers Leaflet, Nature Study, Cornell University, No. 4, March 27, 1897. Parsons, H. G., Children's Gardens for Pleasure, Health, and Educa- tion. Crosby, "School Exercises in Plant Production," Farmers Bulletin 408, U. S. Department of Agriculture. Brady, L. A., " Commercializing the Wonderful Genius of Luther Burbank." The Alcolm, January, 1910. Weed, C. M., and Emerson, The School Garden. lies, George, " Teaching Farmers' Children on the Ground." World's Work, May, 1903. Lyle, " Plant Breeding in a Dutch Garden." Everybody's Magazine, June, 1902. Plant Breeding, Articles as follows: Webber and Bessey, Year- book, Department of Agriculture, for 1899. Hays, Yearbook, Department of Agriculture, for 1901. Bailey, World's Work, 1902, p. 1209. Wickson, Sunset Magazine, December, 1901, February, 1903, April, 1902. Har- wood, Scribner's, May, 1904. Gardner, Cosmopolitan, July, 1904. Bailey, Country Life in America, July, 1903. PHYSIOLOGICAL PROCESSES IN PLANTS 73 Corn Culture and Breeding: Thirteenth Report Kansas Board of Agriculture, XVIII, 785-817. Bulletin 82, Illinois Agricultural Experi- ment Station, 525-539. Hadley, Yearbook, Department of Agriculture, 1902. Harwood, World's Work, September, 1902. Shamel, Cosmo- politan, May, 1903. PROBLEM XIV A study of the structure and work of roots. Materials. — A number of bean, pea, and corn seedlings. * A pocket garden. ROOT SYSTEMS Observation. — Carefully wash the roots of the bean seed- ling. Find a long main root (primary root) that is but a con- tinuation of the lower stem. Find other roots (secondary roots) that are branches of the primary root. Other small branches (rootlets) may also be readily seen. Do the roots all take one general direction ? Conclusions. — 1. What reason can you give for the arrange- ment of roots as you find them ? 2. Why do roots not have such a definite shape as the stem ? a. Factors influencing Direction of Growth 1. EFFECT OF GRAVITY Note. — The pulling force of the earth is known as the force of gravity. Observation. — Sprout some seeds in a pocket garden until the roots are a half inch or so in length, then turn the garden one fourth way around and examine again in a day or so. Results? A growing plant in a pot may also be inverted and the effect on the stem and roots noted. 1 A pocket garden may be made as follows : — Get a couple of 4 x 5 negative plates, clean them, and cut 5 pieces of blotting paper about i inch smaller than the glasses. Lay the blotters on one of the plates, and cut four s-inch strips of wood so as to just fit on the glass outside the blotters. Moisten the blotters, place some well-soaked seeds of mustard, barley, or radish on them, cover the seeds with the other glass, and bind the glasses together with bicycle tape. 74 PHYSIOLOGICAL PROCESSES IN PLANTS Conclusion. — What influence do you think the force of gravity has on roots ? 2. EFFECT OF MOISTURE Observation. — Plant soaked mustard or radish seeds on the outer side of a moist sponge and suspend it under a bell jar where there is plenty of light and moderate temperature. Observe results. Conclusions. — 1. What effect does moisture have on grow- ing roots ? 2. W'hich influence seems to be the more powerful, mois- ture or gravity ? b. Structure 1. BOOT HAIRS Method. — Sow radish seeds on moist earth in a pan, or next to the glass sides of a funnel, so that as the rootlets develop, they may be seen. Or, put a cutting, as tradescantia, in a bottle of water, and note the fine fuzzy growths on the rootlets. Observations. — 1. Find fuzzy, hairlike whitish structures on the root- lets. They are called root hairs. Where are they the longest ? Where the most abundant ? 2. Examine them with the low power of a microscope. Are their walls thick or thin ? Conclusions. — 1. Tell fully just what you think is the pur- pose (function) of root hairs. 2. Why should root hairs be thin ? Note. — Root hairs increase the absorbing surface of roots from 50 to 100 times. 2. FLESHY ROOTS Method. — Cut a cross section through a fleshy root as a car- rot or parsnip (taproot) and dip in iodine. Also cut a length- wise section, and stain. Observations. — 1. What part is stained the most, the outer part (cortex) or the inner part (central or woody cylinder) ? 2. Find some small whitish branches or cores of wood run- PHYSIOLOGICAL PROCESSES IN PLANTS 75 ning from the woody cylinder towards the surface through the cortex. These connect with the root hairs on the rootlets, and are modified cells that form continuous hollow tubes. They are known as fibrovascu- lar bundles. 3. Examine figure of across section of a taproot (Fig. 16). Note that the root hairs are but hollow extensions of cells (epidermal cells) on the outer margins of roots or rootlets. Conclusions. — 1. Which part of a taproot contains Stored-up food (starch) ? Ex- FlG- 16. -Cross section of young root, plain your answer. 2. What seems to be the a, root hair; &, epidermis ; c, corti- cal layer ; d, fibrovascular bundle. use of fibrovascular bundles in roots? c. Root Hairs (Optional Home Work) Observations. — 1. Remove a geranium or other plant from the soil. Pull the roots bearing root hairs through the hand m such a way that the root hairs will be injured. Also allow some of them to dry. Repot the plant and water it. Note the effect after a few hours. After a day or so. 2. Remove and repot another similar plant, taking care to keep root hairs moist and uninjured. Water it. Note the effect as above. 3. Which plant wilts more than the other ? Sooner than the other ? 4. Do both plants regain their normal condition at the same time ? Conclusion. — What do you conclude is one function of root hairs ? d. How Root Hairs absorb Soil Water 1. OSMOSIS AND.EOOT HAIRS Note. — The process by which two fluids or gases separated by a membrane pass through the membrane and mix is called osmosis. Method. — Make an artificial root hair by emptying the coiv 76 PHYSIOLOGICAL PROCESSES IN PLANTS tents of an egg through a small hole at one end ; place the shell in a tumbler and cover with weak hydrochloric acid or vinegar. (Fill the shell with water so that it will sink.) When the shell is dissolved away, fasten the membrane to a J-inch glass tube as shown in Figure 17, by using a few turns of string or a rubber band. Place it under water and blow gently in the FIG. 17. — Experiments to show osmosis. tube to see if there are any leaks. If there are none, pour into the tube enough strong sirup (made of glucose and water) to fill it to a point a little above the membrane. Submerge in water, as in Figure 17, so that the two liquids are at a level. The membrane may well represent a root hair, or cell, and the glass tube one of the tubes of a fibrovascular bundle of a root. The experiment may be varied by setting it up as in Hunter, Elements of Biology, page 89. In many respects this is preferable, as the white of an egg is much like protoplasm or the living matter in cells. Artificial root hairs may also be made by pouring a small amount of celloidin or of collodion in a i-dram tube-vial and tipping it about so that the contents are hardened into a thin PHYSIOLOGICAL PROCESSES IN PLANTS 77 layer within the vial, and then removing it and fastening it to the glass tube as for the egg membrane. Or fasten it to a rubber stopper into which a glass tube has been inserted. Observation. — Are there any changes in level in the two liquids ? Which one, if any ? Conclusions. — 1. Has the water in the jar penetrated the membrane ? How do you know ? 2. Has any glucose passed through the egg membrane into the water ? (Test the water in the tumbler with Fehling's solution for an answer.) 3. If time permits, try making the liquid in the tumbler denser than that in the membrane, and see whether the ex- change is now more rapid in the opposite direction. Is the greater flow towards or away from the thicker (denser) fluid ? 4. How do roots get water and soluble salts from the soil? 5. Show how such substances would likely be forced up in the stem. 6. Why should the soil where seedlings are growing be mellow, or loose and porous ? 7. Expose a pot of wet soil to the direct action of the sun for a few days. Do likewise with another pot of soil but cover it with loose grass or straw to form a mulch. Which pot has the most porous soil at the end of the period ? Which sort of soil will remain the more porous — that naturally covered with grass, leaves, etc., or mulched, or that exposed to the direct rays of the sun ? Show how one sort of soil needs breaking up or tilling more than the other. 8. Why is it that plants need fine loose soil for their root hairs ? 9. Why do plants wilt when first transplanted, and later recover ? 10. Show how liquid foods might get from food tubes into near-by blood tubes. 11. Show how oxygen of the air might get from the lungs into near-by blood tubes. 78 PHYSIOLOGICAL PROCESSES IN PLANTS Questions 1. Why should a farmer cultivate or till the soil ? 2. What is the purpose of mulching the soil ? 3. How deep has the mesquite or sagebush been known to send its roots after moisture ? Where does it grow ? 4. What harm would likely result to trees if the paving and sidewalks should be built up closely about them ? 5. Would potted plants be likely to thrive well if the hole in the bottom of the pot was kept plugged up? Explain. 6. Explain the truth of the following : " Perfect agriculture is the true foundation of trade and industry, — it is the foun- dation of the riches of states." References Hunter, Essentials of Biology. Chap. VII. Coulter, Barnes, and Cowles, A Textbook of Botany. Vol. I, pp. 302- 317. Wilkinson, J. W., Practical Agriculture. Bailey, "Going back to the Old Farm.1' Country Life in America, September, 1904. Bailey, " New Ideals in the Improvement of Plants." Country Life in America, July, 1903. Marcusson, " Exploring for New American Crops." World's Work, September, 1906, December, 1909. Brannon, " Higher Education and the Farm." Educational Review, December, 1909. : Collingwood, H. W., "Back to the Land." Metropolitan Magazine, June, 1910. Burroughs, " Making a Living from the Soil." Colliers, May 14, 1910. PROBLEM XV A. study of some of the relations between roots and the soil. a. Origin of Soil 1. MINERAL MATTER Method. — Put some iron tacks in enough water to cover about half of them. Set aside then and observe them for a few days. PHYSIOLOGICAL PROCESSES IN PLANTS 79 Observations. — 1. What has happened to the tacks ? 2. Examine some sand with a hand lens. Also examine some soil in the same way. What do you observe ? Conclusions. — 1. Could other minerals be affected in the same way as the iron ? What would be the result ? 2. Show how iron might become a part of the soil. 3. How does freezing and thawing affect soil and rock? 4. What happens when glaciers grind rock against rock ? 5. What happens when waves dash against rocks ? When water runs swiftly over rocks ? 6. Summarize the various sources of mineral matter in soil. 2. ORGANIC MATTER Observation. — Examine some loam and soil collected from beneath trees. Conclusion. — What else evidently constitutes part of the soil ? Reasons. b. Kinds of Soil Method. — Take a pound of rich mold from under forest trees, a like amount of rich loam from beneath this mold (black soil), and the same amount from a barren roadside or field. Dry them. Place them on a pie tin or piece of sheet iron, and heat them red hot over a gas stove or coal fire until all that will burn seems to be burned up. Re weigh each sam- ple. Put what remains in bottles and give them to the school museum, if you desire, after labeling them. Observations. — 1. Tabulate results as follows : — EIOH MOLD BLACK SOIL BARKEN SOIL Original weight Weight after burning .... Loss in weight 2. Note the final appearance of the samples. Conclusions. — 1. What do the losses in weight indicate ? 80 PHYSIOLOGICAL PROCESSES IN PLANTS 2. Which sort of soil is richest in organic matter? Inorganic matter ? c. Water-retaining Ability of Soil Method. — Take J pound each of gravel, sand, barren soil (clay), rich loam, leaf mold, and TL- pound of dry leaves. B C D E F FIG. 18. — Experiment to show kind of soil which best retains water. A, gravel; £, sand; C, barren soil; D, rich soil; E, leaf mold; F, dry leaves. Thoroughly dry before weighing. Now place the samples as shown in Figure 18, shake them down, and slowly pour J pint of water on each. Measure all that runs through and tabulate results as follows : — Observation. — Amount of water left in soils. GRAVEL SAND CLAY RICH LOAM LEAF MOLD LEAVES Amount of water added . . Amount of water caught . Amount left in soils . . . Conclusions. — 1. In which sorts of soil would roots best get their water supply ? 2. Is the forest floor of leaves and loam of any importance in retaining the water of rain or snow ? Explain. 3. What would likely be the character of the water drained from such forest floors ? 4. What is indicated by muddy streams ? By the muddi- ness of the Missouri River ? PHYSIOLOGICAL PROCESSES IN PLANTS 81 5. What sort of soil permits of the most rapid evaporation of water? 6. What is the main cause of many million dollars worth of expense to the governments and cities in dredging out and repair- ing harbors? How might much of this expense be saved ? 7. What is the main cause of dry springs and wells in many districts ? 8. Why is it important that the regions of the sources of streams and rivers be forest clad ? 9. What is the main cause of many disastrous floods and freshets ? d. Necessity for Organic Matter Method. — Fill three pots, one with clay subsoil, the second with fertilizer, and the third with humus. Plant some corn or barley in each. Give equal light and care and observe the growth from time to time. Observation. — Which shows the most vigorous growth after two weeks' time ? Conclusions. — 1. WThat is the relation of humus (organic matter) to the growth of plants ? 2. What is one of the necessary conditions for a fertile soil ? e. Necessity for Mineral Matter Method. — Partly fill four quart fruit jars, one with distilled water, the second with nutrient solution1 without calcium phos- phate, the third with nutrient solution without ferric chloride, and the fourth with nutrient solution. Place bean or corn 1 A nutrient solution known as Sach's Solution may be made as follows : — Potassium Nitrate 1.00 gram Sodium Chloride 0.50 gram Calcium Sulphate 0.50 gram Magnesium Sulphate 0.50 gram Calcium Phosphate . . . ...... . 0.50 gram Ferric Chloride . . . . ". . . . . . . 0.005 gram Distilled Water . ',, .... . . . . . 1000.00 grams Add the ferric chloride at the time the solution is to be used, by adding a drop or so to the solution in the bottle used for the seedlings. SHARPE'S LAB. MAN. — 6 82 PHYSIOLOGICAL PROCESSES IN PLANTS seedlings in the jars so that their roots extend down into the liquids. Or better, put cuttings of tradescantia in the liquids. Observe the growths for two or three weeks. Observation. — Which jar shows the most vigorous growth? Conclusions. — 1. What else do plants need besides water, air, moderate temperature, and organic matter (humus) in order to live ? 2. Write a paragraph summing up the factors that make soil fertile. 1. ANOTHER USE OF ROOT HAIRS (OPTIONAL) Method. — Grow a number of radish seeds in a pocket garden. Place a sheet of blue litmus paper so that the growing roots will he against it. Observation. — Observe them from time to time. Does any change of color take place ? If so, what ? Note. — Blue litmus paper will turn red whenever an acid comes in contact with it, while red litmus paper will turn blue whenever an alka- line substance comes in contact with it. (The instructor should here demonstrate these changes.) Conclusions. — 1. Do root hairs give off an acid or alkaline substance ? Explain. Note. — Many mineral substances are dissolved by the action of an acid, as carbonic acid in the soil, from roots. The minerals mentioned in the formula for making nutrient solution are some of them, such as calcium, iron, sodium, etc. 2. Try dissolving some calcium phosphate in distilled water. Result ? Now add a few drops of hydrochloric acid or sulphuric acid. Is there any difference in result ? What ? 3. See if you can now tell another indirect use of root hairs. f. Root Tubercles Method. — Carefully remove the roots from a clover plant, or alfalfa, or vetch. If these cannot well be obtained, use a well- developed bean seedling. Wash the roots carefully. When they are dry, look for nodules, or small wartlike growths on them. Observation. — Describe the appearance of the nodules. Where are they located? PHYSIOLOGICAL PROCESSES IN PLANTS 83 Note. — Root tubercles are small, knotty, wartlike growths that form on the roots of such plants as clover, vetch, alfalfa, pea, "bean, cowpea, soja bean, etc. These tubercles are the homes of germs or bacteria. Their life activities enrich the soil by the addition of much-needed nitro- gen, which these germs obtain from the air and store in their root homes. Plants are unable to obtain nitrogen from the air without their aid, although, as we have learned, the air is about four fifths ni- trogen. Humus, ma- nures, and decaying organic matter con- tain nitrogen in such shape that plants may use it. But these are \ sometimes difficult to FIG. 19. —Roots of red clover with nodules which get and are relatively are the homes of bacteria which enable the expensive plant to use the nitr°Sen of the air- Conclusion. — What should be done by farmers and gardeners in order to increase the supply of available nitrogen in the soil ? What are the advantages of this method ? g. Effect of Crops on Soil Observation. — Copy Figure 20 in your notebook, using different colored crayons, if possible, to represent the phos- phoric acid, potash, and nitrogen. This and the two following diagrams show the amounts of phosphoric acid, potash, and 84 PHYSIOLOGICAL PROCESSES IN PLANTS nitrogen removed from the soil by 1000 pounds each of the different crops mentioned. Each square indicates a pound. ~] - , .£•;?:;•'. \ It z m t 13' 1 jv -:'•' 1 ! 1 . > : | -'- ™ l» FIG. 20. — Showing the pounds of plant, food removed by 1000 pounds of Vir- ginia leaf tobacco, and by 1000 pounds of clover. Conclusions. — 1. How does clover compare with tobacco as a user of nitrogen? 2. If 1000 pounds of average barnyard manure contains about 5 pounds of nitrogen, how much manure will be re- quired to replace the nitrogen removed by 1000 pounds of tobacco ? Observations. — 1. Which of the crops shown in Figure 21 reduce soil fertility the most rapidly ? Ind VAieat Oats FIG. 21. — Showing the amounts of the three most important plant foods that are removed from the soil by 1000 pounds each of the grain of Indian corn, wheat, and oats. 2. How many pounds of nitrogen are removed by 1000 pounds of each of the three crops shown? PHYSIOLOGICAL PROCESSES IN PLANTS 85 3. How does the amount of nitrogen removed compare with the amounts of the other substances ? Conclusion. — Compute the amount of manure necessary to offset the nitrogen removed by each of the grains mentioned. Mi lie (Strawberries FIG. 22. — Showing the amounts of nitrogen, phosphoric acid, and potash re- moved from the soil when 1000 pounds each of beef, milk, and butter are sold. Observations. — 1. How does beef compare with wheat as a remover of nitrogen? 2. How does dairying compare with crop raising as a re- mover of nitrogen ? Conclusions. — 1. As a- rule, which do you consider the more expensive operations, — crop raising or dairying? Note. — We must remember that total costs depend on the amount of plant food removed, the labor required, and the mar- ket price. 2. Suggest two means of returning nitrogen to soil that has been exhausted by repeated crops of the grains.1 h. Crop Rotation Observations. — 1. What would be the advantage of planting rows of cowpeas between rows of corn after the corn no longer needs cultivating ? 2. Many farmers, plow grain stubble under in the autumn, and immediately plant some tubercle-bearing plant. Explain. 1 Supplies of nitrogen bacteria may be obtained for experimental purposes by applying to the United States Department of Agriculture, Washington, D.C. Directions for carrying on the experiments accompany the supplies. 86 PHYSIOLOGICAL PROCESSES IN PLANTS Conclusion. — Show why it is important that grain crops alternate with tubercle-bearing crops. Note. — A regular order of crops, commonly including some tubercle-bearing crops, is known as crop rotation. Observations. — 1. Study the following four systems of crop rotation and see if you can justify them. IBT YEAR 2o TEAR 3n TEAR 4TH TEAR 5rn YEAR 6TH TEAR TTH TEAR a Clover Potatoes Winter Wheat Clover b Corn Corn Wheat or Timothy and Timothy and Timothy and Corn Oats Clover Clover Clover c Corn Oats Wheat Timothy and Timothy and Corn Clover Clover Clover Clover Clover d Potatoes Corn Corn and and and Potatoes Grass Grass Grass 2. Which crops are nitrogen gatherers? Which for cash income? 3. Why is it that tubercle-bearing crops will grow where ordinary grain and garden crops fail ? Conclusion. — Explain fully just what is meant by crop rota- tion. Why is it of supreme importance to man ? Questions 1. Name some roots of commercial importance. Why are they important? 2. Why do some plants store up food in their roots ? 3. What are water roots ? Air roots ? 4. What are parasitic roots ? Give examples. PHYSIOLOGICAL PROCESSES IN PLANTS 87 5. How are the roots of such plants as the dandelion and rhubarb protected from animals ? 6. What insect damages the roots of the grape in Europe? 7. What are the advantages of tilling the soil ? 8. What sort of soil is favorable to evaporation? 9. What is the relationship of tubercle-bearing plants to man's supply of food ? 10. What results from the congestion of population in cities ? 11. Why does such a man as J. J. Hill plead that the people " go back to the soil " ? 12. Give a method of analyzing soils. 13. Wrhat compound of nitrogen is washed into the soil from the air by rains and snows ? 14. What is mulching, and why is it done? 15. Why should the top layer of soil be loose where crops are growing ? 16. WThy are the grain crops relatively expensive crops for the farmer to grow ? 17. What else do plants need from the soil besides nitrogen ? What acid in the soil aids plants in absorbing these substances? References (Also see Prob. XIII) Hunter, Essentials of Biology. Chap. VII. Goff and Mayne, First Principles of Agriculture. Wilkinson, Practical Agriculture. Bailey, Principles of Agriculture. Chaps. V, VI. Osterhout, Experiments with Plants. Chap. III. Moore, G. T., " Soil Inoculation." Century Magazine, p. 831, October. 1904. " Soil Inoculation for Legumes." U. S. Department of Agricul- ture, Bulletin 71, 1905. Bailey, "The Rotation of Crops." Cosmopolitan Magazine, Vol. 38, pp. 682-688, April, 1905. Hunt, "The Importance of Nitrogen in the Growth of Plants." Cor- nell University Bulletin, Experiment Station, No. 247, June, 1907. Laut, "The New Spirit of the Farm." Outing Magazine, May and September, 1908. (Spraying and Bacterial Inoculation. ) 88 PHYSIOLOGICAL PROCESSES IN PLANTS Burkett, "What Crops to grow and how to put the Land in Condi- tion." Country Life in America, p. 255, January, 1905. Snyder, Harry, " What Science does for Farm Crops." Harpers' Mag- azine, October, 1907. Brannon, "Higher Education on the Farm." Educational Review, December, 1909. Clinton, "Soil, what it Does." Cornell University Nature Study quarterly, No. 2, October, 1909. Tarr, "A Handful of Soil." Cornell University Nature Study Quar- terly, No. 2, October, 1899. Durham, " Agricultural Awakening of the South." The Progress Mag- azine, September, 1910. Conn, Agricultural Bacteriology. Knapp, "The Agricultural Revolution." World's Work, July, 1906. Lyon and Byzzell, " Some Conditions favoring Nitrification in Soils." Science, Nov. 26, 1909, p. 773. Hawley, "The Vital Facts of Agriculture, III. The Peculiar Art of Liming Soils." Country Life in America, May, 1905. Miller, "The Awakening of Agriculture." Country Life in America, November, 1904. Chamberlain, " Soil Wastage." Popular Science Monthly, 1908. McLennan, John, A Manual of Practical Farming. Jenkins, W. H., "Keeping up Fertility." Garden Magazine — Farm- ing, June, 1910. Burkett, ' ' The Vital Facts of Agriculture. ' ' Country Life in America, January, 1905. Draper, Dr. A. S., Agriculture and its Educational Needs. Hollister, " Can Intensive Farming be made Practical, etc., for the In- experienced Man from the City ? " The Craftsman, July, 1908. Massey, W. F., Practical Farming. Lipman, Bacteria in Relation to Country Life. Corbett, L. C., "The Propagation of Plants." Farmers' Bulletin No. 157, U. S. Department of Agriculture, 1909. Briggs and others, "The Centrifugal Method of Soil Analysis." Bul- letin No. 24, Bureau of Soils, U. S. Department of Agriculture, 1904. Murray, Soils and Manures. D. Van Nostrand and Co., 1910. Hall, "The Soil as a Battle Ground." Harpers' Magazine, October, 1910. Fairchild, D., "The New Hope of Farmers." World's Work, July, 1906. Quick, " Desert Farming without Irrigation." World's Work, Au- gust, 1906. PHYSIOLOGICAL PROCESSES IN PLANTS 89 Upham, A. A., An Introduction to Agriculture. "Bacteria and the Nitrogen Problem." Reprint Yearbook, U. S. Department of Agriculture, 1902. Rowe, "Raising Germs for Profit." Pearson's Magazine, April, 1910. Plunkett, Horace, Sir, The Bural Life Problem in the United States. Seton, E. T., " Gophers as Soil Formers." Century Magazine, June, 1904. Carpenter, Facts for Farmers. Adams, Cyrus C., "The Ravages of the Sea." Munsey's Magazine, June, 1910. Nature Study on the Farm. Home Nature Study Course, No. 1, Cor- nell University, October and November, 1905. Martin, "The Work of the Brook." Cornell University Nature Study Quarterly, No. 5, June, 1900. Tarr, R. S., "A Summer Shower." Cornell University Bulletin No. 1, June, 1899. Field, G. W., Scientific Agriculture. Report of the Rhode Island Board of Agriculture, 1896. "Beans and Peas for Fertilizer." Long Island Agronomist, No. 8, Nov. 3, 1909. (Huntington, L. I.) Baldwin, "The Human Side of Farming." The Outlook, Aug. 27, 1910. PROBLEM XVI (Optional) A study of buds and their relation to the growing plant. Materials. — Winter branch of horse-chestnut, lilac, or similar plants. Brussels sprouts or cabbage. Winter branches of horse-chestnut or lilac in water in a moderately warm room. a. Buds Observations. — 1. Where do you find buds located ? 2. Where are the buds the larger, — along the sides (lateral buds) or at the tip (terminal buds) ? 3. How many terminal buds on the end of the stem of the horse- chestnut ? Of the lilac ? 4. Find scales on the outside of the horse-chestnut buds. Remove them. Describe their appearance and arrangement. Describe the ap- pearance of the stem where they were removed. 5. Find a ring of scars just below the buds, 90 PHYSIOLOGICAL PROCESSES IN PLANTS Conclusions. — 1. What seems to be the purpose of the sticky material on the bud scales of horse-chestnut ? 2. What do you think the old ring of scars represents ? The new ring of scars ? 3. Of what use is the overlapping of bud scales ? Observations. — 1. What is the appearance of the inner part of the bud ? 2. Where are the inner parts of the bud attached ? Conclusions. — 1. What structures are contained in the bud ? 2. What is gained by having these structures well developed in the bud? 3. How do the structures stowed away in the horse-chestnut bud compare with those in the lilac ? What is the object of the rolling or fold- ing? 4. Why are the buds that live but one year unprotected ? 5. Would tropical trees be as likely to have buds protected as those in colder regions ? Explain. 6. Why do most of our common plants have buds ? 7. What would happen if a plant had no buds ? Explain. Observations. — 1. Examine the opening buds of the winter twigs pre- viously placed in water. What do you find ? 2. Find fresh scars. What do they represent ? 3. Cut a Brussels sprout or a cabbage head lengthwise through the mid- dle. Explain what you see. Are there any protecting scales ? Is there astern? Conclusions. — 1. What structures are contained in the bud ? 2. Why are buds of plants that produce seeds the first year and then die, unprotected ? 3. Name some buds useful as food. PROBLEM XVII The structure and work of stems. Note. — A stem is a developed bud. a. External Structure of a Dicotyledon (Optional) Materials. — Stems of horse-chestnut, lilac, etc. Observation. — Find leaf scars or traces above the buds, along the sides of the stem. What do they represent ? Do you find small scars here arranged somewhat horseshoe-shaped? If so, they are the broken ends of the hollow tubes (fibro vascular bundles) mentioned under the study of root hairs. We found them to originate in the root hairs, from PHYSIOLOGICAL PROCESSES IN PLANTS 91 whence they run up through the stem to the leaves, where they spread to form the veins of the leaf. They conduct fluids containing dissolved food matter from the roots to the leaves, and from the leaves to the stem and root. These tubes are closed when the leaves fall in the autumn. Can you tell why ? b. Lenticels Observation. — Look for small openings or cracks in the bark (len- ticels). These permit the passage of air, and are therefore breathing holes through the bark. Are there few or many ? Conclusions. — 1. If there are also breathing holes in the leaf, when are the lenticels of most importance to a plant ? 2. Would there probably be as many lenticels in evergreen or tropical plants? Explain. c. Internal Structure of a Dicotyledon Observations. — 1. Cut a cross section of box elder or horse- chestnut twig, or other similar stem. How does the inner part (pith) differ from the circle bounding it (wood) ? 2. Which is the stronger, pith or wood ? Which is the most porous ? 3. Find lines radiating from the pith through the wood (medu llary rays) . These serve as channels of communication between the pith or wood cells and the cells of the outer portion of the stem — even the lenticels. They thus convey oxygen as well as food (sugar and water) to the interior of the stem. 4. Just outside the FIG. 23. — Cross section of twig of box elder wood, find the bark. three years old. Note three annual growth Strip off a bit of it. Can rings in, *?" vascular .cylinder" c' cortex ; „ ra, medullary or pith rays; w, wood. you find fibrous structures (After Coulter.) 92 PHYSIOLOGICAL PROCESSES IN PLANTS (bast) (best seen in old bark) ? Just outside this may be found the rind or cortex. In most stems this is made up in part of an outer layer of cork. Conclusions. — 1. Can you think of any use for the woody part of the stem ? 2. Review the function of the medullary rays. 3. (Home work) A potato is an underground stem. How can you tell ? Select two potatoes of unequal weight. Peel one of them until it weighs as much as the other. Set both in a warm place, and after a day or so reweigh. Results ? What is one of the uses of the epidermis of a stem ? Would the corky layer do likewise ? d. Circulation in Stems 1. THE UPWARD PATH OF RAW FOOD MATERIAL Observation. — Get an entire plant with a taproot, as a parsnip. Cut off the root tip, and place the cut end in a solu- tion of red ink or eosine. Let it stand a number of hours and observe the cut end. Cut various sections of the- root and stem and see if you can trace the path of liquids to the leaves. Try the same with sections of a corn stalk. Conclusion. — Where are the tubes (fibrovascular bundles) through which liquids rise situated ? Note. — A stem with fibrovascular bundles arranged as in the box elder or horse-chestnut is characteristic of plants with two cotyledons in the seed (dicotyledons). Stems with these bun- dles scattered through the pith as in the corn are characteristic of plants with one cotyledon in the seed (monocotyledons). 2. THE DOWNWARD PATH OF RAW FOOD MATERIAL Note. — Start this experiment two or three weeks ahead of the time needed. Observations. — 1. Place some fresh willow twigs in water until they form roots. Girdle them (remove rings of bark about PHYSIOLOGICAL PROCESSES IN PLANTS 93 1 inch wide) about one inch from the cut end. Observe results for several days. 2. What happens just above the girdle? What effect on the roots below the girdle ? Conclusions. — 1. Is the path of soil water, etc., interfered with by gir- dling ? 2. Can food material pass from the leaves, etc., back to the roots, when the stem is girdled? Keasons? 3. Is the path of the soil water therefore within the stem proper or in the inner layer of bark ? 4. Is the path of the formed food (as sugar, etc.) therefore within the stem proper, or the inner layer of bark? 5. Explain Figure 24, writing a FIG. 24. —Diagram to show paragraph of description. the resions in the stem through which the raw food materials pass up the stem, and food made in the leaf passes down the stem. (Af- ter Stevens.) e: Condition of Food passing through the Stem Method. — Half fill a tube with starch and water, and another with glucose and water. Put both tubes in a vessel of water as indicated, with the water on a level with the liquids in the tubes. After FIG. 25. -Experiment showing the os- a day or so test the ]iquids in mosis of sugar, and the non-osmosis ,, -, £ , , £ of starch, a, tube with starch and the V6SSels f°r starch aild f°r water ; 6, tube with sugar and water. Sugar. 94 PHYSIOLOGICAL PROCESSES IN PLANTS Observations. — 1. Which tube shows the greatest change in level ? 2. Which test was successful, for the starch or for the sugar ? Conclusions. — 1. Which substance was able to pass through the membrane ? 2. Which one of the two is already soluble ? 3. How might you change (digest) insoluble starch to soluble sugar? (See experiment, digestion in the corn grain, Prob. X.) 4. In what form must insoluble starch pass back and forth through the stem, and from cell to cell through cell walls ? f. How Stems protect Themselves (Optional) PRICKLES, SPINES, THORNS, ETC. BITTER AND POISONOUS SUBSTANCES FLINTY, ETC. HUGGING THE GROUND Fill in the above table with as many plants as you can find that protect themselves as indicated at the top of the columns. Write a paragraph, summing up the information tabulated. Questions 1. What are the uses to the plant of each of the parts shown in a cross section of a woody stem ? 2. Where is the upward and downward path of liquids through a woody stem ? Of a pithy stem ? 3. What is the condition of food as it passes through the stem ? 4. Mention some special uses to man of stems. 5. What is meant by grafting ? Budding ? 6. What are some of the methods of cutting timber ? 7. What is the function of fibrovascular bundles ? PHYSIOLOGICAL PROCESSES IN PLANTS 95 Special Reports 1. Some methods of keeping forests. 2. Some methods of cutting timber. 3. Circulation through stems. References Hunter, Essentials of Biology. Chap. VIII. Problem XVIII A study of leaves in relation to their environment. a. Reactions of Stems and Leaves to Light Observations. — 1. Place some plants near a light window. Observe them for a few days. 2. Place a potted plant in a dark place for a number of days. Observe as above. Conclusions. — 1. What conclusions can you make with refer- ence to the effect of light on leaves and sterns ? 2. Why are leaves spread out so as to fill in all intervening spaces (mosaics) ? b. Structure 1. STOMATA Observations. — 1. Strip off a bit of the under surface of a leaf such as the onion, geranium, lily, or tradescantia, and ex- amine with the low power of a FlG £6._stomataof epidermis >< portable microscope. Find num- lower surface of a leaf, e, epi- bers of small oval structures dermal cell ; .. The purpose of grafting ? How is it done ? PHYSIOLOGICAL PROCESSES IN PLANTS 109 6. What is grafting wax ? How is it made ? 7. What is budding ? How is it done ? 8. Name some steins useful to man. 9. Name some stem products useful to man. 10. Name some twining stems. Some fleshy stems. 11. The uses of rattan and bamboo. 12. The storage of starch in stems. 13. The effect of girdling stems. 14. What is the cambium layer ? 15. How may stems protect themselves ? 16. WThy are the forests and streams of Maine of more worth than her agricultural resources ? 17. Why should Victor Hugo say, "For the world lets everything perish which is nothing but selfishness — everything that does not represent an idea or a benefit for the human race " ? Special Reports 1. History and origin of the potato. 2. Commercial products from stems. 3. The big trees of California. 4. Methods of forest preservation. 5. The manufacture of paper from stems. 6. Stems used as food. 7. Government field work in forestry. 8. Plant propagation by stems. References Hunter, Essentials of Biology, Chaps. VIII, X. Osterhout, Experiments with Plants. Chap. V. Taylor, "Street Trees, Care and Preservation." Cornell University, Agricultural Bulletin 256, June, 1908. Pinchot, "The Forest Service." U. S. Department of Agriculture, Cir- cular 36, 1906. Commercial Tree Studies. U. S. Department Agriculture, Forestry Service, Bulletins 13, 22, 31, 33, 37, 38, 53, 58, and 64. Hough, " The Slaughter of the Trees." Evenjbodifs Magazine, May, 1908. Pinchot, " Primer of Forestry." Farmers' Bulletin 173, U. S. Depart- ment of Agriculture. 110 PHYSIOLOGICAL PROCESSES IN PLANTS "Tree Planting in Rural School Grounds." Farmers' Bulletin 134, U. S. Department of Agriculture. " Clearing New Land." Farmers' Bulletin 150, U. S. Department of Agriculture. Roosevelt and others, "Forests and Timber Supply." Forestry Cir- cular 25, U. S. Department of Agriculture. " Rubber Culture for Porto Rico.'1 Botanical Circular 28, U. S. De- partment of Agriculture. 44 Maple Sugar and Syrup.1' Farmers' Bulletin 252, U. S. Department of Agriculture. "Camphor Tree." Botanical Circular 12, U. S. Department of Agri- culture. " Hemp Industry in the United States." Yearbook, 1901, U. S. De- partment of Agriculture. Whipple and Wilson, "The Part played by the Forests in Everyday Life." Suburban Life, April, 1908. "Coal as a Commercial Factor." Metropolitan Magazine, March, 1909. Treadwell, A., "A Primer of Conservatism." Circular 157, Forest Service, U. S. Department of Agriculture, 1908. Fernow, B. E., Care of Trees in Street, Lawn, and Park. "National Forestry Map." Supt. of Documents, Washington, D.C. 50^. Weed, Our Trees and how to know Them. Winkerwerder, "Forestry in the Public Schools." Circularise, For- est Service, U. S. Department of Agriculture, 1907. Fernow, B. E., A Brief History of Forestry in Europe. "Wood Distillation." Forestry Circular 114, U. S. Department of Agriculture. "Forestry in Public Schools." Forestry Circular 130, U. S. Depart- ment of Agriculture. " Forest Fires in the Adirondacks." Forestry Circular 26, U. S. De- partment of Agriculture. " Waning Hardwood Supply of the Appalachian Forests." Forestry Circular 116, U. S. Department of Agriculture. Roosevelt and others, "Forest Preservation and National Prosperity. " Forestry Circular 25, U. S. Department of Agriculture. Fernow, "History of Forestry." Forestry Quarterly, Cambridge, Mass., 1910. Bailey, L. H., "Trees in Winter, how they Look." Teachers'1 Leaf- lets, Nature Study, No. 12, Cornell University, January 1899. Huntington. A. O., Studies of Trees in Winter. PHYSIOLOGICAL PROCESSES IN PLANTS 111 Keeler, Our Northern Shrubs and how to identify Them. Our Native Trees and how to identify Them. Rogers, J.E., Trees Every Child should Know. Wyman, A. P., " Leaves and Acorns of our Common Oaks." Teachers' Leaflet, Nature Study, No. 8, Cornell University, September, 1897. Graves, G. S., "The Advance of Forestry in the United States." Review of Reviews, April, 1910. Newell, F. H., "The Reclamation of the West." Annual Report Smithsonian Institution, 1904, p. 827. Burba, G. F., "Tree Surgery." Pearson's Magazine, April, 1910. Burroughs, John, "The True Test of Nature Literature." Country Life in America, May, 1904. "Songs of Nature," Country Life in America, December, 1906. Finch, William C., Water. PROBLEM XX (Optional) Some forms of plant life with special reference to nutrition and reproduction. a. An Alga Pond Scum (Spirogyra) 1. GENERAL Method. — Mount some of the material in water and study with low power of a microscope. Observations. — 1. What is the shape of a single plant ? Note. — A threadlike body is called a filament. 2. Is it one-celled or many-celled ? 3. Can you find any roots or leaves ? 4. What is the color ? What are plants that contain chlorophyll able to manufacture ? Conclusions. — 1. Would you consider this plant to be simple or complex ? 2. Show if any part corresponds in function to leaves. 2. EEPRODUCTION (a) Sexual Observations. — 1. Find filaments joined so as to form ladder-like structures. Here cells send out tubes which connect with similar tubes 112 PHYSIOLOGICAL PROCESSES IN PLANTS from the neighboring cells of another filament, so that the contents of one cell may pass over and mix with the contents of another. This is a sexual method of reproduction. The part passing over is said to be the supplying or male gamete, while the part to which it fuses is called the receiving or female gamete. 2. Can you find any cells emptied of their contents ? If so, what do you find in the neighboring cell ? Note. — The result of conjugation or the union of the male and female gametes is to form a new cell, called a spore (zygo- spore, or yoke spore). The receiving gamete is said to be fertilized. 3. Can you find any such spores ? If so, do they have thin or thick walls about them ? Note. — These spores are also said to be "resting spores " and correspond to seeds. The outer coat en- ables them to resist freezing, drying, etc. Like seeds, they sprout whenever the conditions are favorable. Conclusions. — 1. Explain how these plants survive the drying up of ponds in summer, or the cold of winter. 2. Write a paragraph on the sexual method of re- ^w production in Spirogyra. — =-| I 3. Write another paragraph on the advantages of FIG 31 — Coniuga- tlie sexua^ method of reproduction in Spirogyra. tion of Spirogyra. /, fusion in prog- (&) Asexual ress; zs, zygo- _^o«e. —The filaments of these plants break into parts at certain times, and these parts form new plants. This method of producing new plants is called asexual reproduc- tion. b. A Fungus Materials. — Ordinary mold on decaying fruits and vegetables, or on bread. Observations. — 1. What is the color of the mold ? 2. Does it contain chlorophyll ? Conclusion. — Can this plant manufacture its own food ? Note. — Plants unable to manufacture their own food are much like animals in that respect. If they live directly on living plants or animals they are said to be parasites, while if they obtain their food from dead bodies or organic wastes, as the molds do, then they are said to be saprophytes. PHYSIOLOGICAL PROCESSES IN PLANTS 113 Observations. — 1. Find tiny bodies on stalks (spore cases or spo- rangia). (Use low power of microscope.) 2. Some of these sporangia may be broken open by pressing on the cover glass. Can you find small spherical bodies (spores') therein ? Conclusions. — 1. What method of repro- duction is here repre- sented, the asexual (veg- etative), or the sexual? Explain. 2. Do you judge these spores were formed by cell union or cell divi- sion f Explain. Observations. — 1. (Dem.) Search deep in FlG" 32. -Conjugation of mold, a, 6, c, d, suc- cessive stages in the formation of the zygo- spore, zs. zs the mold for large dark bodies (zygospores) , formed where the tubes from mold filaments meet. 2. Study Figure 32. What resemblance shown to reproduction in Spirogyra ? Conclusions. — 1. What method of reproduction is here illustrated ? 2. What must evidently be the purpose of the zygospores here ? (See Spirogyra.) c. A Moss Observations. — 1. Examine specimens of any kind of moss — prefera- bly pigeon wheat moss. Do you find root, stem, and leaves ? 2. Is there chlorophyll present ? Conclusion. — Is this plant able to manufacture its own food (independ- ent) or does it use food already made (dependent) ? Observations. — 1. Find tiny capsules at the tips of slender stalks. How are they covered ? 2. Crush one on a slide and examine it with low power. What do the capsules contain ? Conclusion. — What method of reproduction is here evidently shown ? Note. — The capsule is on a stalk, which is rooted in the tip of the leafy plant. It is in reality a separate plant, but with no leaves of its own. Where, then, must it get its food ? Is it a parasite ? Observation. — Refer to charts, models, or slides. What results from the sprouting of a moss spore? Note. — The asexual spore grows SHARPE'S LAB. MAN. — 8 114 PHYSIOLOGICAL PROCESSES IN PLANTS into a threadlike plant, which finally develops into a leafy moss plant. This produces sex organs at its tip, which correspond to the anthers and pistils of an ordinary flower. An anther-like organ is called an antheridium and produces male cells called antherozoids, corresponding to pollen. These are able to swim (motile} in water, however. A pistil-like organ (archegonium) contains a single, comparatively large female cell, called an egg. Conclusions. — 1 . By what means must the male cell reach the egg ? 2. What method of generation is here illustrated ? Explain. 3. When an asexual generation is followed by a sexual one, it is called alternation of generations. Show how it is illustrated here. d. A Fern Observations. — 1. Observe a common fern plant. Are there root, stem, and leaf ? 2. What is the color ? Conclusion. — Could this plant be called a parasite ? A saprophyte ? Explain. Observations. — 1. Look on the under side of the leaves for small fruit dots, or spore cases. How are they distributed ? Note. — Plants producing asexual spores are called spore plants, or sporophytes. Those producing sexual spores (gametes) are known as gametophytes. 2. Crush a spore case on a slide and examine it with low power. (A good figure or chart may suffice.) What is the form of the spores ? Conclusion. — What method of reproduction is here shown? Ex- plain. Observations. — 1. Refer to a good figure or chart, and find what develops from the growth of an asexual spore. Does it have roots ? 2. Find organs corresponding to anthers and pistils on the small plant (prothallus) which grows from the spore. Just where are they located ? Note. — The anther- FIG. 33. — A, Archegonium of fern; c, . ,. J canal ; e, egg. S, antheridium, which ldia and archegoma are here much produces male fertilizing cells; C, an- as in the moss' The male cells therozoid or male fertilizing cell, are able to swim in ram or dew, highly magnified. (After Strasburger.) so that they may reach the egg. PHYSIOLOGICAL PROCESSES IN PLANTS 115 Conclusions. — 1. What generation does the prothallus represent ? Explain. 2. Show how there is alternation of generations. Observations. — 1. Study Figure 33. Just where is the egg cell located ? 2. Just how must the antherozoid or sperm cell (0) reach the egg cell (e) ? Conclusions. — 1. Does the process of fertilization here take place internally or externally ? Explain. 2. Show if it is of any advantage to an egg cell that it be reached only through a small tube. 3. Could the egg cell be fertilized if the archegonial tube was perfectly dry ? Explain. 4. Fill in the following summary : PLANTS WAYS SPERM CELLS KEACII THE EGG SKETCHES Spirogvra Mold Moss Fern . Tulip . . . . ... Questions 1. Explain the term ' alternation of generations.' 2. What advantages result from alternation of generations ? 3. Are ferns independent or dependent plants ? Explain. 4. Which method of reproduction better enables a plant to fight adverse conditions ? Which for rapid and easy multiplication ? 5. What disadvantages to a moss plant that the sporophyte be de- pendent on the leafy plant (gametophyte) ? What advantages ? 6. What conditions favor the growth of molds ? 7. What is meant by vegetative or asexual reproduction ? By sexual reproduction ? 8. What is a sporophyte ? Give an example. A gametophyte ? Example ? 0. What are parasitic plants ? Example ? Saprophytic ? Example ? 10. What is the essential process of fertilization ? 11. Why must male germ cells be so much more abundant than eggs ? 12. Why must plants and animals reproduce themselves ? 116 PHYSIOLOGICAL PROCESSES IN PLANTS 13. Why are male fertilizing cells so much smaller than eggs ? Note. — Water plants set sperm and eggs free in the water, where fertilization takes place and the resulting spore (seed) usually sinks to the bottom to germinate when conditions are right. 14. Why must mosses, ferns, etc., protect their eggs until and after fertilization ? How is this accomplished ? Special Reports 1. The advantages and disadvantages of alternation of generations. 2. Means of overcoming unfavorable conditions of development. 3. The importance of protecting the egg. 4. Ways in which sperm cells reach the egg. 5. The main differences between algae and fungi. References Hunter, Essentials of Biology. Chap. XI. Leavitt, Outlines of Botany. §§480-484. PROBLEM XXI (Optional) A study of the way plants are modified by their sur- roundings. (A field trip.) INTRODUCTION Note. — Most plants must have soil, water, light, air, and proper tem- perature in order to grow. Plants use these factors in different propor- tions, so are organized into groups or societies, which express their relations to these different factors. As the relation or reaction to water is perhaps as evident and universal as any, it is commonly used as the basis of grouping. Thus there are : — a. Hydrophytes, or water plants, or groups. b. Xerophytes, or those in sandy, rocky, or other dry places. c. Mesophytes, or those intermediate between water plants and those of dry regions. Other divisions may be also made on a temperature or on a soil basis. The above societies may be further subdivided into swamp society, pond society, rock society, sand society, meadow society, thicket society, prairie society, forest society, etc., or they may take their names from the most conspicuous plant present, as an oak, cactus, or water lily society. PHYSIOLOGICAL PROCESSES IN PLANTS 117 a. Hydrophyte Society Observations. — 1. Select any region where there is a pond, marsh, or running water, and plenty of water plants. Find out the names of the plants, if you can; if not, give any common names, or describe them as best you can. Are there few or many plants ? FIG. 34. — Photograph of plant societies, vegetation. Note the different zones of 2. Are there any plants entirely submerged? Any floating? Do any rise in the air ? 3. What differences between submerged leaves and those exposed to the air ? 4. How do the roots of plants entirely free from the soil differ from ordinary roots? Conclusions. — 1. Are submerged leaves affected by sun exposure ? If not, do they need to be as entire and fleshy ? Explain. 2. How must floating plants obtain their supply of soil substance ? 3. What takes the place of leaves in the algalike plants ? Observations. — 1. Cut off the stems of some of the larger water plants, and note their interior structure. How would you describe it ? 2. Look for stomata with a hand lens, — or after returning from your 118 PHYSIOLOGICAL PROCESSES IN PLANTS trip. Look especially on the leaves of such plants as the water lily. Are they on the upper or lower side of the leaves ? Conclusions. — 1. Is a stem of spongy tissue well or poorly adapted to permit air from the water to reach its interior ? 2. What advantage in the stomata being on the upper side of a leaf ? Observation. — Pull up one of the rooted plants. How do they differ from any near-by land plant ? How do the roots of each differ ? Conclusion. — What seem to be the main functions of the roots of such water plants ? b. Xerophyte Society Observations. — (Study such plants as the cactus, rubber plant, and century plant. If none are growing wild, visit greenhouses.) 1* What is the character of the soil, — sand, rock, or clay, etc.? 2. Find water content as under mesophytes (meadow). 3. What plants do you find ? Which are the most abundant ? 4. Pull up some of the plants and examine the roots, if growing wild. How do they compare with those of mesophytes ? Hydrophytes ? Conclusion. — Why do these plants need long roots ? Observations. — 1. Do all of these plants have leaves ? If so, how do they compare in thickness and width with mesophytic plants ? Hydro- phytic ? Conclusions. — 1. Why should xerophy tic plants either be leafless, or with leaves usually thick and fleshy ? 2. If no leaves are present, what is the character of the stem ? c. Mesophyte Society 1. MEADOW Observations. — 1. Collect a sample of the soil in a pint fruit jar. Bring it to the laboratory and get the weight of the sample. Then dry the sample thoroughly, using slow heat. What is the weight of the soil water in your sample ? What is the percentage of water (water content) in the meadow soil ? 2. Get the names of all the plants growing here that you can. Are they few or abundant ? 3. Pull up a few of the plants and note their roots. How do they dif- fer from those of the hydrophytes ? Do you find root hairs ? Conclusions. — 1. Can you think of any reason why the roots of meadow mesophytes should be better developed than those of hydro- phytes ? PHYSIOLOGICAL PROCESSES IN PLANTS 119 2. Do you think the water content of the soil is such as to satisfy a hydrophyte ? Observation. — Cut off the stems of some of these plants. Is their structure more or less spongy than hydrophytes ? Conclusion. — Are the stems of meadow rnesophytes more or less able to serve as supporting organs as compared with the stems of hydrophytes ? Observations. — 1. Note the number of leaves. Are they more or less abundant than with hydrophytes ? 2. Note the fleshiness, thickness, and breadth of the leaves. How do they compare with hydrophytes ? Conclusion. — Show whether the leaves of hydrophytes would be well or poorly adapted to carry on the work required of them by meadow mesophytes. (Refer to pages 1 02-103 : Means of protection against enemies, climate, etc.) Observation. — Look for stomata. On which side of the leaf do you find them ? Conclusions. — 1. How do the locations of stomata in these plants com- pare with those of hydrophytes ? Any reason for different locations ? 2. Do you think the plants you have studied are perfectly adapted to their habitat ? Give reasons. Note. — If plants are not well adapted to their environment, they will be stunted in growth, reproduce themselves poorly, and be easily killed or driven out. 3. Do you think any of these plants could live about as readily in any other habitat as in a hydrophytic or xerophytic region ? That is, are plants always killed out if they do not readily find their special habitat ? May such a plant as a willow flourish as a hydrophyte if such a habitat should accidentally be thrust upon it ? 2. FOREST 1. Thickets. 2. Deciduous forests. 3. Evergreen forests. Method. — Follow the same method of procedure as for meadow. 3. SANDY PLAIN OB SANDY ROADSIDE Method. — As for meadow. d. Summary Observations. — 1, Fill in the following tabulation, as far as possible : 120 PHYSIOLOGICAL PROCESSES IN PLANTS PLANT SOCIETIES CHARACTER OF LAND SOME TYPICAL PLANTS CHARACTER OF STEM CHARACTER OF LEAVES CHARACTER OF KOOTS RELA- TION TO MAN Xerophytes . . . Mesophytes (a-) Meadow . (6) Forest . . (c) Sandy plain Hydrophytes . . FIG. 35. — Diagram of zonation about a pond. I, pond; II, bog zone; III swampy thicket zone ; IV, incomplete zone in barren soil of a sand pit ; V, dry meadow zone; VI, dry woodland zone. (After Bergen and Davis.) PHYSIOLOGICAL PROCESSES IN PLANTS 121 e. Plant Zonation Observations. — 1. Show how the distribution of plants depends largely on the character of the ground they occupy. 2. How do meadow and forest formations differ ? Sea beach from swamp ? Swamp from pond ? 3. Study Figure 35. Note the subdivisions into zones. How many are there ? How are they named ? Conclusion. — What factor has evidently caused most of the differences in the characters of the zones ? Observation. — Using Figure 35 as a model, make a study of any pond formation and try to make a similar diagram. Conclusion. — Report your observations, including as many names of plants as possible, also differences in appearance between the zones, etc. Thus : FLESHY PLANTS ROOTED — SUBMERGED ROOTED, BUT PART IN AIR PLANTS MOSTLY IN AIR PLANTS ALL IN AIR Questions 1. Show how plant societies depend on the variations in surroundings (physiographic conditions). 2. Which of the plant societies is most directly concerned with man's welfare ? 3. Why were the valleys of the Euphrates and the Kile centers of early civilization ? 4. What part of the United States is the most productive ? Why? 5. Explain the advantages of irrigation in such states as Colorado, Utah, and Arizona, 122 PHYSIOLOGICAL PROCESSES IN PLANTS 6. What, is meant by the "timber line"? Under what conditions does it exist? 7. Where are the conditions the more variable, in the arc- tics or tropics ? Then -where would there be more variation in plant life ? 8. As ponds dry up, do different plant societies follow one another ? Explain. 9. How does the arctic willow vary from its relative of the temperate zone ? Why ? 10. How do floating plants get their supply of soil substance ? 11. Where are there xerophytic forests in the United States ? 12. What are halophy tes ? What are their characteristics ? Special Reports 1. The factors that determine plant association. 2. How plants protect themselves from drought. 3. The effect of cold regions on plants. References Hunter, Essentials of Biology. Chap. XII. Coulter, Text-book of Botany. Chaps. XXI, XXII, XXIII, XXIV. Bergen and Davis, Principles of Botany. Chaps. XXXVI, XXXVII. Weed, C. M., Wild Flower Families. Bailey, L. H., "How Plants Live Together." Cornell University Nature Study Quarterly, No. 6, October, 1900. Merriam, C. H., "Life Zones and Crop Zones in the United States." Bulletin 10, U. S. Department of Agriculture, 1898. THE BIOLOGICAL INTERRELATIONS OF PLANTS AND ANIMALS PROBLEM XXII Some relations of fungi to man. a. Conditions and Results of the Growth of Yeast 1. FOOD Method. — Mix part of a cake of compressed yeast in a little water to form a thin paste. Prepare five wide-mouthed bottles, labeling them 1 to 5. In No. 1 put some yeast and water. In No. 2 put some yeast and some molasses or glucose. Set the two bottles aside in a moderately warm place and ob- serve after 24 hours. Observations. — 1. What is the smell and taste of No. 1 ? 2. What is the color in No. 1 ? 3. What are the smell, taste, and color of No. 2 ? Conclusions. — 1. What evidence is there that the yeast is working in one of the bottles ? Which one ? 2. What is one of the conditions necessary for the growth of yeast ? 2. TEMPERATURE Observations. — 1. Pour some of the mixture from bottle No. 2 into bottles Nos. 3 and 4. Set No. 3 aside in a jar of cracked ice or in a refrigerator. Result in a few hours ? 2. Set No. 4 in a jar of boiling water, and heat it to boiling. Set it aside to cool. Result ? Conclusion. — Name some conditions of temperature harmful to the growth of yeast. 123 124 INTERRELATIONS OF PLANTS AND ANIMALS 3. RESULTS OF GROWTH Observations. — 1. Loosely stopper a bottle containing grow- ing yeast. Draw out some of the gas above the yeast by means of a large bnlb pipette and bubble the gas through lime- water. Result ? 2. Show how, when yeast is put into dough, the conditions of its growth are present. 3. What gas must be set free in the dough ? 4. What happens when yeast acts in sugar ? Note. — The name of this process is fermentation. Conclusions. — 1. What causes bread to rise ? 2. Why does bread " fall " if not baked soon after it has risen ? 3. Why set the dough in a warm place for rising ? b. Some Economic Relations of Other Fungi Observation. — Tabulate the information called for in the following table, so far as you are able : FUNGI NAMES How USEFUL How HARMFUL Yeast Molds . . . Corn Smut Mushrooms Bracket Fungus Wheat Rust Potato Scab . . Questions 1. What becomes of the alcohol produced by using yeast in dough ? 2. Explain the use of yeast in bread making. INTERRELATIONS OF PLANTS AND ANIMALS 125 3. Why use yeast in wine making ? Beer making ? 4. Are there yeast plants in the air ? How can you prove it ? Special Reports 1. Bread making. 2. The brewing industry. 3. Some useful fungi. 4. Some harmful fungi. 5. The wheat rust. 6. The corn smut. 7. The chestnut fungus. References Hunter, Essentials of Biology. Chap. XIII. Hunter, Elements of Biology. Chap. XI. Conn, Bacteria, Yeast, and Molds in the Home. PROBLEM XXIII A study of bacteria, and of some of their relations to man. a. Conditions of Growth Materials. — One pint of fresh milk, box of cracked ice. Nutrient gelatine in tubes as put up by Parke, Davis & Co. Some sterilized Petri dishes with covers. Some sterilized flasks and corks. (Sterilize them by boiling them in water for fifteen minutes.) Alcohol lamp or Bunsen burner. Observations. — 1. Pour equal amounts of milk into each of 3 flasks. Label them 1, 2, and 3. Cork No. 1 and set it aside in a moderately warm room. Cork No. 2 and place it in an ice box or in cracked ice. Boil the milk in No. 3 for half an hour, plug the flask with sterilized cotton, and set it with flask No. 1. Are there any differences in smell and taste in the course of a few days ? 2. Put some nutrient solution in each of three sterilized Petri dishes. Label them 1, 2, and 3. Expose No. 1 to the dusty air of a room for a few minutes. Cover it and set it aside in a shady warm place. Examine it after a day or so. Is there any noticeable effect on the gelatine ? 126 INTERRELATIONS OF PLANTS AND ANIMALS 3. Place No. 2 in direct sunlight as much as possible. (Keep it moderately cool.) Results as before ? 4. Place No. 3 uncovered but in a very dry place for a few days. Results ? Conclusions. — 1. What effect have dark warm places on the growth of bacteria ? 2. What effect has sunlight on the growth of bacteria ? Lack of moisture ? 3. What conditions favor the growth of bacteria ? 4. What are some of the conditions that retard or hinder the growth of bacteria ? 5. What causes food to spoil ? 6. Name some of the various ways of preserving food. Ex- plain just why they may be successful. b. Some Relations to Man 1. PUTREFACTION OR DECAY Materials. — Hay infusion, beef juice, microscope, slides, charts or figures of bacteria. Observations. — 1. Make a hay infusion by pouring some hot water on some chopped-up hay in a quart jar, and allowing to stand a day or so in a warm place. What changes in color do you observe ? Note. — There must have been some germs on the hay that developed as soon as it was warm and moist enough. These germs must have survived the hot water, and after it was the right temperature, developed rapidly, feeding on the infusion from the hay. 2. Prepare some beef juice and set it aside in a warm place, in a beaker. After a day or so note any changes in color and odor. 3. Examine a drop from each of the preparations with at least a J-inch objective, — use a higher power if possible. Do you see any signs of life ? Compare them with Figure 36. Conclusions. — 1. What do you think caused the hay and the beef juice to change their color and odor (decay or putrefy)? INTERRELATIONS OF PLANTS AND ANIMALS 127 2. What would happen if organic matter did not decay ? 3. May these bacteria be useful or harmful to man? FlG- ^- — Useful bacteria which change dead mat- „ * „ i -r-r. , ter into food for grass, wheat, and corn. Highly magnified. 2. SOME OTHER USEFUL BACTERIA Observations. — 1. Set aside some cream in a moderately warm place for a day or so. Results ? Odor and taste ? 2. Squeeze some juice from apples. Set it aside as above. Results? 3. Set aside some fresh grape juice as above. Results? 4. Bruise an ap- ple or banana. Set it aside in a moder- fltP warm nlsPA for duv5 \\ dl 111 IJlciOc i-UL several days. Re- suits ? 5. Explain how linen fibers are prepared. 6. Which sort of cheese is considered the better, that freshly made or that aged ? Explain. 7. What causes nodules to form on the roots of such plants as clover, alfalfa, bean, etc.? (See page 82.) Conclusions. — 1. What is the benefit of ripening or souring cream ? What has probably caused it to do so ? 2. What is the result of the action of bacteria on the alcohol of fruit juices ? Note. — The alcohol was formed by the action of yeast from the air or on the fruit, fermenting the sweet juices, resulting in cider, wine, etc. The alcohol is then attacked by bacteria, which change it into an acid (acetic acid) 3. WThat is meant by decay? Note. — An example of decay of starch might be represented as follows : Decay = Starch 4- oxygen = carbon dioxide -f- water C,H1005 + 6 02 = 6 C02 + 5 H20 128 INTERRELATIONS OF PLANTS AND ANIMALS The growth of the same starch may be represented as follows : Growth = Carbon dioxide + water = starch -f free oxygen 6 C02 + 5H20 = C6H1005 + 6 02 4. What is meant by ' fertilizing the soil ' ? 5. What would happen to the plant nourishment in the soil if there were no decaying organic matter to add to it ? 6. Write a paragraph, telling how some bacteria may be useful to man. 7. Write another paragraph, showing that but for useful bacteria the world would be a desert, and man himself could not exist. c. Some Methods of Fighting Harmful Bacteria 1. DISINFECTION OR STERILIZATION Materials. — Nutrient gelatine or agar-agar, milk, 5% carbolic acid, 4% formalin, and lysol if possible. Steam or hot air steri- lizer. Ice box or cracked ice. Observations. — 1. Inoculate each of six tubes of gelatine with bacteria by touching colonies of bacterial growth with a sterilized platinum wire or a needle, and transferring to the gelatine. Cork each one with sterilized cotton. Label the tubes 1 to 6. Place No. 1 in a warm place. What is the result in three days ? Five days ? 2. Cover the surface of No. 2 with carbolic acid solution, seal, and set it in a warm place. What are the results in three days ? Five days ? 3. Cover the surface of No. 3 with 4 % formalin and set it in a warm place. What are the results in three days ? Five days? 4. Cover the surface of No. 4 with corrosive sublimate solu- tion. What are the results in three days ? Five days ? 5. Cover No. 5 with 70% alcohol, and set it in a warm place. What are the results in three days ? Five days ? 6. Sterilize No. 6 in the sterilizer for one half hour. Seal at INTERRELATIONS OF PLANTS AND ANIMALS 129 once and set it in a warm place. Observe the results in three days. Five days. 7. Seal No. 7 and place it in an ice box or in cracked ice. Observe the results in three days. Five days. 8. Tabulate your results as follows : 1. 2. 3. 4. 5. 6. 7. 8. NORMAL GROWTH CARBOLIC ACID FORMALIN CORROS. SUB. ALCOHOL HIGH TEMP. Low TEMP. EXTRA NOTES Appearance in 3 days Appearance in 5 days Conclusions. — 1. Which of the above methods of disinfection do you think is the best ? Why ? 2. Why is it necessary to heat foods before canning them ? 3. Why is hay dried before it is put into the barn ? 4. Why put foods in the refrigerator in the summer time ? 5. What conditions hinder the growth of bacteria ? 2. PASTEURIZATION Note. — Pasteurization is the heating of a substance to about 160° F. long enough to kill most of the germs. Materials. — One pint of milk, two sterilized fruit or agate jars, thermometer, alcohol lamp or Bunsen burner, double cooker or hot air sterilizer. Note. — Special pasteurization apparatus as shown in Figure 37 may be procured for a small sum. Observations. — 1. Put a half pint of milk in one of the sterilized fruit jars, and set it uncovered in a warm place. Result after two days ? Taste, odor, etc. ? 2. Place a half pint of milk in another of the sterilized jars (or it may be placed in the inner vessel of a double cooker that SHARPE'S LAB. MAN. — 9 130 INTERRELATIONS OF PLANTS AND ANIMALS has been sterilized). Set it in a vessel of boiling water just removed from the flame, and heat it to 150-160° F. or 66-72° C., stirring with a clean spoon for 10 minutes. Let it remain for 15 minutes, then quickly cool. Set it aside with the other jar, and compare them after a day or so. Re- sult ? Taste, odor, etc.? Which is the sweeter tasting? Which has the sweeter odor ? Which is there- fore purer, or freer of germs ? Note. — Discontinu- ous sterilization or pas- teurization may be per- formed by heating the FIG. 37. — Pasteurizing apparatus. substance to be sterilized twice a day just as for ordinary ster- ilization. Continue thus for two or three days. Why ? Conclusions. — 1. How may milk be pasteurized ? 2. What is the benefit of pasteurization ? 3. Why should milk be marketed in bottles ? Observations. — 1. Carefully pour the milk from the pail or bottle at home, after it has stood several hours, and see if there is any sediment left. Result ? 2. Taste the milk used at home. Does it leave a slightly unpleasant taste, reminding one of the odor about cow barns ? If so, the milk should be pasteurized before using. Note. — Boiling may do, but it renders it somewhat more difficult of digestion and also changes the taste, so that it is especially distasteful to some ; therefore pasteurization is to be preferred. Conclusions. — 1. What do you think the sediment in milk is likely to be ? 2. Would there likely be bacteria in the filth in which cows*Tiave been lying ? Observations. — 1. Rinse out a recently emptied milk bottle INTERRELATIONS OF PLANTS AND ANIMALS 131 with water, stopper, and set it aside in a warm place. Note the odor after 10 or 12 hours. Note. — Any odor will surely indicate the .presence of bacteria, although they may be present without an odor. 2. Rinse another recently emptied milk bottle with cold water, then with boiling water, and finally scald it by boiling it in a pot of water for 5 minutes. Drain it well, stopper it, and set it aside as the first one. Note odor as before. Conclusions. — 1. What care should be observed with vessels that have contained milk ? 2. What is the effect of high temperature on bacteria in milk ? Questions 1. Why coat eggs with paraffin or soluble glass (sodium silicate) ? 2. Why are hams and bacon smoked ? 3. How is it that such an animal as the mammoth has been found entire and in a good state of preservation in Siberia ? 4. Explain the principle of sour and sweet pickles. 5. Explain the advantage of the following method of can- ning fruits. Put fruit and a sufficient amount of sugar to suit in jars, cover them loosely, arid set them in an oven for heat- ing or in a boiler with a few inches of water and boil the water for a half hour. See that the boiler is closed, also that the jars do not stand directly on the bottom of the boiler. Place a cloth under them, or some strips of wood, to prevent breakage. 6. Why should pasteurized milk be cooled at once ? 7. What is the principle of drying foods to make them keep ? 8. Explain the Italian proverb, "Where the sun does not come the doctor does." Special Reports 1 . The importance of decay. 2. Pasteurization. 3. The importance of wholesome milk and how to attain it. 132 INTERRELATIONS OF PLANTS AND ANIMALS 4. Some useful bacteria. 5. Conditions of growth of bacteria. 6. Raising germs for profit. 7. Some common disinfectants. 8. Indispensable bacteria. References (Also see Probs. XIV and LVI) Hunter, Essentials of Biology. Chap. XII. , Elements of Biology. Chap. XI. Davison, The Human Body and Health (Advanced). Conn, Bacteria Yeasts and Molds in the Home. Thompson, W. H., " Indispensable Bacteria " Everybody's Magazine, August, 1909. Rowe, " Raising Germs for Profit." Pearson's Magazine, April, 1910. Elliott, Household Bacteriology. Library of Home Economics, Chi- cago, 1907. Conn, H. W., The Story of Germ Life. Practical Dairy Bacteriology. Bacteria in Milk and its Products. Thomson, W. H., Some Wonders in Biology. Elliott, Moore, and Pierson, Bacteriology of the Household. Cornell University Reading Course, February, 1909. Lipman, Bacteria in Relation to Country Life. Metchnikoff, "The Utility of Lactic Microbes." Century Magazine, November, 1909. Van Rensselaer, Martha, Dust as Related to Food. Cornell University Reading Course, Ser. IV, No. 18, 1905. "Facts about Milk." Farmers' Bulletin No. 2, U. S. Department of Agriculture, Ser. IV, No. 18, 1905. Salmon, "Directions for the Pasteurization of Milk." U. S. Depart- ment of Agriculture, Bureau of Animal Industry, Circular No. 1 (re- vised), 1897. Rogers, " Bacteria in Milk." Reprint from Yearbook of Department of Agriculture for 1907, Washington. Frankland, Mrs. Percy, Bacteria in Daily Life. Conn, Agricultural Bacteriology. Bailey, L. H., " The Making of Clean Milk." Country Life in America, June, 1904. Wells, " Water and Ice Supply." Farmers' Bulletins 43, 73, 262, 309, U. S. Department of Agriculture. INTERRELATIONS OF PLANTS AND ANIMALS 133 Ward, Pure Milk and the Public Health. " Miik and its Products as Carriers of Tuberculous Infection." Circular 143, Bureau of Animal Industry, U. S. Department of Agriculture, 1909. Hall, "The Soil as a Battle Ground." Harper's Magazine, October, 1910. Weyl, W., " Pure Milk and Human Life." Success Magazine, March, 1909. Gulick, L. H., "Constructive Community and Personal Hygiene." Science, May 27, 1910. Dorset, M., "Some Common Disinfectants." Farmers' Bulletin 345, U. S. Department of Agriculture, 1908. I PROBLEM XXIV A study of some biological relations of plants and animals. a. The Balanced Aquarium (A Food Relation) Observations. — 1. What have you learned is formed and set free when water-living plants (algae) are exposed to sunlight ? 2. What do animals need that is commonly obtained from the air ? 3. Do you think that water animals need the same sub- stance ? If so, where might it come from ? 4. What gas is given off from the lungs of man ? Note. — The same gas is given off by all other animals, — by very small animals through the cell wall, by fishes through the gills, etc. 5. Do plants use this gas ? How do they use it ? 6. Animals also give off certain nitrogenous wastes, such as urea and ammonia. Conclusions. — 1. How may the fishes in an aquarium obtain the necessary oxygen for respiration or breathing ? 2. How might the oxygen get into the water ? 3. Where might the plants in an aquarium obtain necessary carbon dioxide ? Nitrogenous matter ? 4. Itemize briefly how the plants and animals of an aqua- rium might be helpful to one another. 134 INTERRELATIONS OF PLANTS AND ANIMALS Observations. — 1. As snails feed on plants, and small water animals and tadpoles may feed on the decaying plant and animal matter that is likely to collect, they may be used as the animal life of a fresh-water aquarium. A small goldfish might also be added. FIG. 38. — A balanced aquarium. 2. As such plants as algae and other water plants grow at least as fast as they are devoured by the snails, it would seem desirable that they be used as the plant life needed. Conclusions. — 1. Fill in the following summary. Do the two columns balance ? 2. What is a ' balanced aquarium ' ? INTERRELATIONS OF PLANTS AND ANIMALS 135 BALANCED AQUARIUM CONTENTS INCOME FROM OUTGO TO Animals « • Plants . . . b. Relations between Green Plants and Animals (The Energy Relation) Observations. — 1. Study Figure 39 carefully. Just what forms the food material of plants possessing chlorophyll ? 2. What forms the food of animals and plants without chlorophyll ? 3. What becomes of the food mentioned in No. 2 ? 4. What are the bacteria of decay ? Carbon dioxide I (C02) Water \ \(H20) Simple Salts Ammoniaj CNHsT Plants with chlorophyll build up complex organic substances They store up energy from the sun in the process and. Carbon dioxide A (C02) Animals and plants without Water X(H20) , chlorophyll m. which tear down complgz Ammonia organic substances ] (NH3) and set free energy in the process in form of heat f food of Energy from su;n. as heat. FIG. 39. — Relations between green plants and animals. (After Colton.) Energy set free as heat. Conclusions. — 1. How are plants able to store up energy ? What finally becomes of it ? 2. What is the energy relation between plants and animals as shown above ? 136 INTERRELATIONS OF PLANTS AND ANIMALS .Animal Life sing Bacteria Nitrites "Nitric Bacteria c. The Nitrogen Cycle (The Nitrogen Relation) Method. — Begin at the statement "Free N." and trace Figure 40 in the direction of the arrows. 1. Where is free nitrogen to be found ? 2. What is the only way that free nitro- gen may be obtained from plants? 3. What do plants manufacture in addi- tion to starch that becomes available for animals ? 4. What waste sub- stance containing nitrogen is being constantly set free from animals? 5. What causes dead animal tissues to break up into their parts ? 6. What are some of these parts ? What becomes of them ? Conclusions. — 1. What are the two most important links or factors in the nitrogen cycle ? 2. Write a paragraph explaining what is meant by the 1 nitrogen cycle.' 3. Try filling out a final summary in tabular form, some- what as follows : — FIG. 40. — The nitrogen cycle. INCOME of ANIMALS FKOM OUTGO FROM ANIMALS TO {Green . . Bacteria . INTERRELATIONS OF PLANTS AND ANIMALS 137 d. A Hay Infusion (Another Food Relation) Observations. — 1. Make a hay infusion as in the preceding problem. Let it stand a few days. What is the change in color ? Appearance ? Odor ? 2. Is there a scum on top ? If so, what does it indicate ? Conclusions. — 1. What is a tea infusion? Similarly, what is a hay infusion? 2. How do you think bacteria came to be in the hay infu- sion ? 3. Where did the bacteria come from? 4. On what may the bacteria feed ? What is the result of their action ? Observations. — 1. With a bulb pipette put a small drop from the scum on a glass slide and examine it with a low power of the microscope. 2. Do you see small one-celled animals moving about ? Note. — If corn meal is scattered on the scum, any small animals present, as paramcecia, will congregate about the meal to feed. Dipping near the bit of meal will then more surely result in getting numbers of paramoecia or other one-celled animals. Conclusions. — 1. Where must the one-celled animals have come from ? Note. — Grass for hay is commonly grown near pools or wet places that dry up about haying time. These places practically always contain one-celled animals (Protozoa) that encyst themselves as they dry up, much as the resting spores of spirogyra or molds do; when this happens, they are blown about with the dust. 2. How do these encysted forms resemble seeds ? 3. What causes seeds to awaken? What then likely caused these little dormant one-celled animals to awaken in the infu- sion ? 4. Write a paragraph telling just why hay is used in the above manner in order to get one-celled animals for study. 138 INTERRELATIONS OF PLANTS AND ANIMALS Special Reports 1. The best aquatic plants. 2. Life in an aquarium. 8. The nitrogen cycle. 4. The balanced aquarium. 6. Life in a hay infusion. 6. Indispensable bacteria. 7. Animal and plant relations. Questions 1. What is the use of chlorophyll to a plant ? 2. Where do animals living in water get their oxygen ? 3. What relations exist between animals and plants in re- gard to food ? 4. Show in detail what is meant by the ' nitrogen cycle.' 5. Only how can plants use the free nitrogen of the air ? 6. What two sorts of bacteria may well be known as in- dispensable? Show why. 7. What substances are set free when animal tissues decay ? 8. Show how paramoecia and other one-celled animals may be obtained in the laboratory. 9. Why do some Protozoa encyst ? 10. Show why marine Protozoa do not need to encyst. 11. What are the relations between the animals and plants in a hay infusion ? References Hunter, Essentials of Biology. Chap. XIV. — Elements of Biology. Chap. XII. Conn, Agricultural Bacteriology, p. 89. Lipman, "Indispensable Bacteria." Everybody's Magazine, August, 1909. Nevins, G. , " The Balanced Aquarium. " Pearson's Magazine, October, 1907. Whedon, C. C., " The Fresh-water Aquarium." Country Life in Amer- ica, January, 1905. Rogers, J. E., "The Salt-water Aquarium." Country Life in Amer- ica, July, 1904, p. 298. INTERRELATIONS OF PLANTS AND ANIMALS 139 Hoard, I)., " How to make a Land and Water Aquarium." Outing Mag- azine, April, 1906. Conard, H. S., "The Best Aquatic Plants." The Garden Magazine, November, 1900, p. 181. Rogers, M. F., "Life In An Aquarium." Teacher's Nature Study Leaflets, No. 11, Cornell University, April, 1898. Jones, T. II., The Aquarian Naturalist. Van Voorst, London, 1858. Murbach, L., " Fresh- water Aquaria." Journal Applied Microscopy, September, 1900, also American Naturalist, March, 1900. Smith, E., The Home Aquarium and How to Care For It. Kellogg, V. L., Elementary Zoology, p. 408. Bristol, C. H., " The New York Aquarium." Popular Science Monthly, February, 1910. Bggeling and Ehrenberg, The Fresh-water Aquarium and its Inhabit- ants. Scherren, II., Ponds and Hock Pools. Hints on Managing Micro- aquaria. Samuel Mark, The Amateur Aquarist. Bateman and Bennett, The Book of Aquaria : Part I, '* Fresh- water Aquaria " ; Part II, " Marine Aquaria." Taylor, J. E., The Aquarium. Baternan, G. C., The Vivarium. Gosse, P. H., The Aquarium. Wood, J. G., The Fresh and Salt Water Aquarium. Humphreys, Noel, Ocean Gardens. Damon, W. E., Ocean Wonders. Furneaux, Life in Ponds and Streams. Mayer, A. G., Seashore Life. The New York Aquarium Nature Series, 1905. Arnold, A. F., The Sea Beach at Ebb Tide. "The Care of Balanced Aquaria." New York Zoological Society Bulletin for April, 1903. Hall, *« The Soil as a Battle Ground." Harper's Magazine, October, 1910. THE PHYSIOLOGICAL UNIT AND DIVISION OF LABOR PROBLEM XXV To study a one-celled anim,al, in order to understand better tJie unit of animal structures. Apparatus. — Pipette, glass slides and cover glasses, and com- pound microscope, charts showing methods of reproduction, etc., hay infusion. Method. — Place some of the cloudy material from an infu- sion of hay or grass on a glass slide, cover with a cover glass, and study with low power of the microscope. (Look for paramcecia.) a. In its Relation to its Surroundings 1. REACTIONS TO STIMULI Observations. — 1. Look carefully for small whitish animals moving rapidly about — much as shown in Figure 41. Do they move with any certain end first ? 2. What shape has one of these animals ? 3. Are they able to bend their bodies ? 4. Do they seem to be able to avoid any obstructions ? 5. Do they seem to congregate in any places in particular ? 6. What seems to be the method of loco- motion ? 1 Note. — Here refer to Figure 41, and find the cilia, or fine vibratory hairlike structures. instructor may demonstrate cilia if time permits, although it is not considered necessary. 140 FIG. 41. — Diagram of a paramoecium. F. V., food vacuole ; C. V., contractile vacuole ; M, mouth ; N, nucleus. (After Sedgwick and Wil- son.) UNIT AND DIVISION OF LABOR 141 * Conclusions. — 1. Does there seem to be an anterior or head end as distinguished from a posterior or tail end ? Explain. 2. Are these animals sensitive to their surroundings ; that is, do they react, or respond, to stimuli ? Reasons for your deci- sion ? 2. FEEDING (OPTIONAL) Note. — The food balls are small masses of food distributed throughout the body. Method. — Run a mixture of carmine and water under the cover glass. Observations. — 1. Look for a diagonal groove where the food is taken in (gullet). 2. Can you make out any movements of cilia here as indicated by the carmine grains ? 3. In course of time, do you find any food balls within the body, as in- dicated by the carmine ? Note. — The masses of food appear to be inclosed in small areas, con- taining fluid, called vacuoles. 3. CONTRACTILE VACUOLES (EXCRETION) (OPTIONAL) Note. — Other vacuoles, round clear openings, besides those containing food, can commonly be seen, which are supposed to act to pass off waste material from the cell body. These are called contractile vacuoles. Observations. — 1. See if you can make out any changes in the shape of these vacuoles. 2. Do they close at times? 4. REPRODUCTION (OPTIONAL) Observations. — 1. Look for animals pinching into two parts, dumbbell fashion. (If the material does not show it, refer to page 192, Hunter, Essentials of Biology.') This is known as reproduction by division. 2. Likewise can you find any fused together lengthwise side by side ? This is known as conjugation. Conclusion. — Sum up the method of reproduction in a paramcecium. b. As a Cell (Optional) Method. — Use prepared slides or Figure 41. Can you find a cell wall ? How can you tell nucleus from cytoplasm ? 142 UNIT AND DIVISION OF LABOR Drawings (Optional) 1. The paramcecium as a cell. Label everything shown. 2. Showing the different methods of reproduction. c. In its Relations to Man Observations. — Fill in the following tabulation as far as possible. See references below. DISEASE MEANS OP TRANSMISSION WHERE FOUND How PREVENT Malaria . ."> . Smallpox . . . Sleeping Sickness . Spotted Fever . Chronic Dysentery Rabies . . . . Measles .... Chicken Pox . . Texas Fever Kala Azar . v. , Nagana .... Surra . Questions 1. What is the meaning of the word Protozoa ? 2. What is a cell ? 3. What is protoplasm ? Nucleus ? Cell wall ? 4. Where are Protozoa found ? 5. How do Protozoa reproduce themselves ? 6. Why are Protozoa so universally distributed ? 7. How do Protozoa get rid of waste ? How eat ? How breathe ? 8. What is meant by encysting ? The purpose of encyst- ing? 9. What is an amoeba ? How does it move, eat, reproduce, and get rid of waste ? UNIT AND DIVISION OF LABOR 143 10. What is said to be the cause of malaria ? 11. What are trypanosomes ? 12. Tell of the use of Protozoa as food. 13. Tell of Protozoa and rock building. What is chalk ? 14. Explain the statement, " The cell is a unit." 15. How do Protozoa respond to stimuli ? 16. Distinguish between Protozoa and Metazoa. 17. Why are Protozoa of great importance to the world ? 18. What is tripoli ? 19. What are parasitic Protozoa ? 20. What is a hay infusion ? 21. Explain: "The basis of all the life in the modern ocean is found in the microorganisms of the surface." Special Reports 1. The formation of chalk. 2. Protozoa and malaria. 3. The tsetse fly and sleeping sickness. 4. Barbados earth. Infusorial earth. 6. The relation of Protozoa to higher forms of life. 6. The importance of Protozoa to man. References Hunter, Essentials of Biology. Chap. XVI. Hunter, Elements of Biology. Chap. XII. Ritchie, Primer of Sanitation. Chap. XXVI. Davison, The Human Body and Health (Advanced). Chap. XXIII. Weeks, "The Practical Side of Mosquito Extermination." Science, Vol. XXIII, p. 379, 1906. Macfayden, The Cell as the Unit of Life. Calkins, G. N., Proto-zoology. PROBLEM XXVI An introductory study of -many-celled animals (Meta- zoa). Method. — Develop the idea of the many-celled gastrula from the fertilized egg by using models, diagrams, etc. 144 UNIT AND DIVISION OF LABOR a. Development Observation. — What is the beginning stage of existence of a fern ? Moss ? Tulip ? Bird ? Conclusions. — 1. Write a paragraph on the subject of Fer- tilization. 2. What must happen to the egg before it will develop ? Note. — You will recall that the sperm cells of the moss and fern are motile, and that the egg is much larger and not motile. Here is a fine example of a physiological (functional) division of labor, which well meets the demand that one con- jugating cell be very motile, and therefore comparatively small. Thus the sperm cells can swim to the eggs in the water where they are commonly set free. Another demand is that there be a sufficient supply of food to enable the plant or animal embryo to develop until such a stage of growth that it may care for itself. So food is stored in the egg, thus making it comparatively large and so hindering any great degree of independent move- ment. Remember that sperm cells and eggs are single cells. Observations. — 1. After fertilization the egg divides into two parts, then these two divide, finally forming four cells, then 8, 16, 32, etc., until it is much like a hollow ball. How many layers of cells are there ? Are the cells now all of the same size ? Note. — The hollow ball stage is known as the blastula stage. See Figure 42. 2. Note that the hollow ball sinks in where the cells are FIG. 42. — Stages in the segmentation of an egg, up to the formation of the gastrula. UNIT AND DIVISION OF LABOR 145 the largest, until the side pushed in reaches the other side, thus forming a cup. How many layers to the walls of the cup? Note. — This stage is known as the gastrula (little stomach) stage, as the inner layer of cells commonly acts as a feeding organ (stomach). Conclusions. — 1. What is the main difference between a single cell and a gastrula ? 2. If the inner layer of cells of a gastrula function as a stomach, where is the mouth ? Note. — Practically all animals above the one-celled ones pass through the stage just men- tioned up to the gastrula stage, and then develop into the special animal concerned. b. Sponges 1. GRANTIA Material. — Small vials of grantia, hand lenses, toilet sponge. Observations. — 1. Find needle-like or bristle-like structures (spicules) forming the skele- ton of the sponge. 2. Can you find a system of canals and cavities for the passage of water ? 3. Find a large opening at the free end (the osculum). /— 4. Examine a sponge split lengthwise, and one cut cross- wise, and find the central space or cloaca. 5. Note the small passage through the body wall lead- „ & J FIG. 43. — Diagram of plan of structure ing from the outer surface to Of a sponge. O, osculum; /, inhalent the central cavity. The ex- pore ; C, cloaca, ternal openings of these canals are called inhalent pores, and the internal openings are called ostia. SHARPE'S LAB. MAN. — 10 146 UNIT AND DIVISION OF LABOR FIG. 44. — Section through sponge wall. Showing fla, flagella, the vibrations of which cause cur- rents of water to flow through the sponge. Conclusions. — 1. What seems to be the . fl a, purpose of the inhal- ent pores? Of the canals ? 2. What is the course of the water through the canals? Refer to Figure 43. 3. What causes the water to flow through the canals ? See Fig- ure 44. 4. How might you compare a sponge with the city of Venice ? 5. Show that special parts of a sponge have special duties (division of labor). 2. OTHER SPOXGES (OPTIONAL) Material. — Small bits of sponge skeletons, slides and cover glasses, portable microscopes, hydrochloric acid, chart. Method. — Mount bits of the skeleton of grantia and a toilet sponge, and examine with low power. Also test them with acid. Observations. — 1. Which spicules are needle-like, and which are much branched ? 2. Which feel the most elastic to the touch ? 3. Which sort of sponge absorbs water the most readily? 4. What is the effect when grantia spicules are put in acid ? The toilet sponge ? When each are burned ? 5. What can you say about the odor of sponges. Conclusions. — 1. Why is the toilet sponge an article of commerce, rather than the other ? 2. How does a sponge appear to be protected from fish and other animals ? c. The Hydra (Optional) Observations. — 1. Observe living hydras, either in a small aquarium or in Syracuse watch glasses. UNIT AND DIVISION OF LABOR 147 2. What is their shape? Note. — Study Figure 45 or a chart. Note that the body of a hydra is hollow, and with but one opening at the free end of the body, that serves both as a mouth and as a means of getting rid of waste. 3. How many threadlike organs (tentacles) do you find about the mouth ? Conclusions. — 1. Compare a hydra with a gastrula, showing how they resemble each other. Note. — The gastrula stage of most water animals is ciliated so that it may swim about until it finally settles down to develop further, — either with very little added differences, as in the hydra, or many added changes in order to form higher and more complicated animals. 2. Study a longitudinal section of a hydra, and show how it is much like a gastrula. 3. Show how certain parts of this animal have certain duties to perform (division of labor). 4. In what respect does a hydra agree with a sponge? 5. Which have the better arrangement for getting food and oxygen, Protozoa living singly, or many ciliated cells side by side, as in the sponge ? Which have better opportunities for development ? FIG. 45. — Lengthwise section of hydra; ba, at- tached end; b, bud ; m, mouth; ov, ovary; sp, spermary holding sperm or male cells. 148 UNIT AND DIVISION OF LABOR d. The Development of Tissues and Organs Observations. — 1. We have previously learned that cells doing the same sort of work are said to form tissues, such as muscle tissue, nerve tissue, protecting tissue, etc. How many FIG. 46. — Different sorts of cells ; some results of division of labor. tissues in agastrula? What are they? Note. — A tissue is a set of similar cells for a special purpose. 2. Examine Figure 46 or slides showing different kinds of cells, such as of muscle, nerve, bone, etc. Are they formed for the same or different functions ? See also Figure 9. 3. What tissues have you noted in a hydra ? 4. Name some tissues that are likely in your hand. Note. — Organs are special sets of tissues, each for a special purpose, as the hand, the eye, the ear, the stomach, etc. Conclusions. — 1. If organs are made of tissues and tissues of cells, what is your conclusion ? 2. What is the purpose of different sorts of cells in the 'body? UNIT AND DIVISION OF LABOR 149 3. Show that, if cells represent soldiers, the body is a well- disciplined army, with many divisions for different sorts of work, — these divisions made of different regiments, but the regiments of individuals working in harmony. e. Common Functions Observations. — 1. What must a one-celled animal do in order to live? (Review paramoecium.) Note. — The necessity for food implies a need of the means for getting it, such as organs of locomotion, nerves, sense organs, etc. After food is obtained it must be digested, then carried about the body (circulation) arid the waste eliminated (excretion), etc. Conclusions. — 1. Name the organs and functions common to all animals so far as you know them. 2. How does a one-celled animal compare with a man in the number of its organs, and, therefore, the degree of bodily or physiological division of labor ? 3. Fill in the following tabulation. Tell means of perform- ing the common functions, as far as possible. COMMON FUNCTIONS PARAMCECIUM SPONGE (OPTION) HYDRA MAN (OPTION) Food taking . . Digestion . . . Circulation . Respiration , •' . Excretion »v .- Locomotion . . Nerve control Senses .... Nerves .... Reproduction 150 UNIT AND DIVISION OF LABOR 4. Which one is the better organized, and therefore the higher animal ? Reasons for your answer ? Questions 1. Where are the sponge cells in an ordinary commercial sponge ? 2. How are toilet sponges prepared for the market ? 3. How and where are toilet sponges obtained ? 4. How do the individual sponge cells get their food and oxygen ? 5. How does a sponge show division of labor ? 6. Where are the most important sponge fisheries ? 7. Tell, step by step, how a fertilized sponge egg becomes a blastula, then a gastrula, and finally a stationary sponge. 8. Show how there is division of labor in a hydra. 9. What are the functions common to all animals ? 10. What is the cell theory ? Special Reports 1. The sponge industry. 2. The development of Metazoa to the gastrula stage. 3. Division of labor in a metazoan. 4. The cell theory of Schleiden and Schwann. References Hunter, Essentials of Biology. Chap. XVI. Elements of Biology. Chap. XIV. Potts, E. Fre.sh-wat&r Sponges, Miner, R. W., A Guide to the Sponge Alcove. Guide Leaflet 23, American Museum of Natural History, New York, October, 1906. Moore, " A Practical Method of Sponge Culture." Bureau of Fisheries. Document 669, 1910. Jordan, Foot-Notes to Evolution. SOME REACTIONS AND ADAPTATIONS AMONG ANIMALS PROBLEM XXVII (OPTIONAL) The relations of the earthworm to its surroundings. Materials. — A shallow tray, moist blotting paper, hand lens, ruler, a pasteboard cover to fit tray, bristles, living earthworms. a. External Appearance Method. — Place living worm in the shallow tray on moist blotting paper. Observations. — 1. Is it an active or sluggish animal ? 2. What is its general color ? 3. What advantage to the worm is the relation of its color to the color of the earth ? 4. What is its general shape ? What is its symmetry ? 5. How should you identify the anterior end ? 6. How does the dorsal surface differ from the ventral surface ? On which surface does the worm crawl ? 7. Find the broad band (girdle} near the anterior end. Conclusions. — 1. How distinguish the anterior from posterior end ? 2. How does the earthworm resemble other animals you have studied ? How does it differ ? 3. How may it escape its enemies ? b. Motions Observations. — 1. Measure the shortest length and the greatest length of the same worm. 2. Examine and compare the regions of expansion and contraction as the worm moves forward. 3. Run your finger lightly over the ventral surface of the worm. What do you feel? (Use specimens preserved either in (1) formalin or (2) alcohol, then dehydrated, then run into xylol, and then dried.) 151 152 SOME REACTIONS AMONG ANIMALS 4. Examine the ventral side with a hand lens and identify the project- ing bristles (setce). Conclusions. — 1. How are contractions and expansions concerned in the forward motions of the worm ? 2. What prevents a worm from slipping while crawling ? c. Nervous Responses to Stimuli Observations. — 1. Gently touch various parts of the worm with a blunt bristle. 2. Observe a moving worm carefully. How does it find its way ? Is the " lip " a sense organ ? 3. Place the worm in a tray and partially cover it with the paste- board cover. Observe whether the worm prefers light or darkness. 4. Tap the tray with your pencil. Does the worm respond ? Conclusions. — 1. What do you think regarding its responses to touch ? 2. What about its responses to light ? 3. Does a worm hear or feel in responding to a jar ? 4. Which portions of a worm are the most sensitive? d. Blood Tubes Observations. — 1. Look for a dorsal red tube which pulsates. This is the dorsal blood vessel which can be seen through the semitransparent body wall. 2. Examine the region about the girdle for several pairs of lateral red vessels, the so-called "hearts." Conclusions. — 1. Does the blood move in any definite direction as indi- cated by the pulsations ? 2. How might oxygen get into the blood tubes you can see ? Questions 1. Why cannot earthworms live in a dry place ? 2. How do earthworms enrich the soil ? 3. Do they injure plants or animals ? 4. How are earthworms protected from their enemies? 5. What is the effect of the parasitic habit on such a worm as the tapeworm ? 6. In what different ways do worms get their food ? 7. What is meant by the term u regeneration " as applied to worms ? 8. What are some of the most dangerous worm parasites to man and the domestic animals ? SOME REACTIONS AMONG ANIMALS 153 Special Reports 1. Economic importance of the earthworm. 2. Economic importance of worms in general. 3. Reactions of the earthworm. References Hunter, Essentials of Biology. Chap. XVII. Ayres, E. A., "Eyes and Vision from Worm to Man." Harper's Magazine, September, 1908. Watson, J. B., "The New Science of Animal Behavior.1' Harper's Magazine, February, 1910. PROBLEM XXVIII U. S. Depart- ment of Agriculture, 1896. BIRDS IN THEIR RELATION TO MAN 217 Hammond, S. T., My Friend the Partridge. Dickerson, M. C., "The Pageant of Nature." Country Life in Amer- ica, November, 1907. Job, H. K., "Our Vanishing Shore Birds." Country Life in America, October, 1906. Weed, C. M., and Dearborn, M., Birds in their Relation to Man. Fisher, A. K., " The Economic Value of Predaceous Birds and Mam- mals." Yearbook, Department of Agriculture, 1908. " You call them thieves and pillagers ; but know They are the winged wardens of your farms, Who from your cornfields drive the insidious foe, And from your harvests keep a hundred harms." — LONGFELLOW. THE HUMAN BODY AS A MACHINE PROBLEM XLI A study of man as a vertebrate compared with a frog. a. Comparisons Observations. — 1. Note that the body of man is divided into two distinct regions, head and trunk. Can you find these in the frog? Is the head movable? How does it differ from that of man ? 2. What is the body covering of the frog ? How does it differ from that of man ? Note. — The sliminess of the skin of the frog is due to some cells that pour out mucus. Conclusions. — 1. Can you think of any use for this secre- tion ? 2. Why should a frog's head be more flattened than that of man ? Observation. - — Note the position of the eyes of a frog. How does it differ from the position of the eyes of man ? Conclusion. — Does a frog need a neck as does man ? Explain. Observations. — 1. Note the divisions of a fore limb or arm, into upper arm (forearm) and hand. How many fingers on each hand ? 2. How do the fore limbs of a man differ from those of a frog? Conclusion. — How do the functions of the hand of a man differ from those of a frog ? Observations. — 1. Find the thigh, shank, and foot in the hind leg of a frog. 2. How many toes on each foot ? How do the hind feet differ from the front ones ? 218 THE HUMAN BODY AS A MACHINE 219 3. How do the ankle and the foot of man differ from those of the frog ? 4. What advantage in the hind legs of a frog being so near the hind end of the body ? Conclusion. — What adaptions for locomotion found in the frog not found in man ? b. A Typical Muscle and its Functions Material. — Hind legs of a frog preserved in 4 % formalin. 1. FROG Method. — Strip off the skin of the hind leg. Observations. — 1. Note the whitish muscle that forms the calf. Is it in a solid mass or in bundles ? 2. Where is it widest ? The wide part is called the belly. 3. Look carefully for the endings. Where are they fas- tened ? The glistening white part which attaches a muscle to a bone is called a tendon. 4. Pull the large muscle in the calf. What movements result ? 5. How are the muscles related to one another ? Conclusions. — 1. What results when a muscle contracts? 2. Should both muscles of a pair contract at once ? If so, what would happen ? 3. Why is it necessary that muscles be arranged in pairs ? 4. What is the advantage of a tendon ? 2. THE HUMAN BODY Method. — Grasp the upper right arm with the left hand. Raise and lower the forearm a number of times. Find the muscles that form the pair for moving the forearm. Observations. — 1. Which one is the larger ? Why ? 2. What changes take place in the muscles of the arm as they are used ? Conclusions. — 1. What happens to a muscle when it shortens ? 2. WThat happens to bones when muscles shorten ? 220 THE HUMAN BODY AS A MACHINE 3. MUSCLES AS PART OF A MACHINE Note. — The instructor should here briefly explain the principle of the lever, as well as the three classes or kinds. Designate them by the fac- tor placed in the middle. Method a. — Kaise a book in the right hand. Observation. — Locate the power, weight, and fulcrum. What represents each ? Use Figure 53 in locating P, W, and F. Conclusion. — What class of lever is represented here ? (Make a sketch to show your conclusion.) Method b. — Stand on tip- toe. Observations. — 1. What is the effect on the muscle in the calf of the leg ? 2. Locate weight, ful- crum, and power. Conclusion. — What class of levers represented here ? Make a sketch to show your conclusion. \ FIG. 53. — Diagram showing action of biceps muscle, a, contracted; b, ex- tended ; h, humerus ; s, scapula. A B 4 C FIG. 54. — Forms of levers. A, first class; B, second class; (7, third class; W, weight; F, fulcrum or pivot; P,pull or power. THE HUMAN BODY AS A MACHINE 221 Method c. — Bend the head backward. Observations. — 1. Where is the muscle located that pulls the head backward ? 2. Locate the power, weight, and fulcrum. Conclusions. — 1. What class of levers is represented here ? Make a sketch to show your conclusion. 2. Show that all three classes of levers are in the foot. 4. MICROSCOPIC STRUCTURE (OPTIONAL) Materials. — Boiled lean beef, microscope slides, portable or stationary compound microscope, and hand lens. Method a. — Try pulling the lean beef in strips. Also examine with hand lens. Observations. — 1. What is the structure of the muscle ? 2. Find thin whitish bai^ds scattered throughout the muscle. Describe their appearance. Conclusions. — 1. How are the fibers of muscles held in place ? 2. Compare these fibers with bundles of rubber bands. Method b. — Examine a bit of muscle with low power of a compound microscope. Observation. — What do you see concerning the structure of muscle, not seen well with the hand lens ? Can you make out the fibers ? Conclusion. — What is lean meat ? What is its structure ? c. General Adaptations of the Skeleton Materials. — Shank bones of calves or sheep from the market — some sawed crosswise, others lengthwise, skeleton of frog or other vertebrate, skeleton of man, charts, HC1, Bunsen burner or alcohol lamp, crucible, scales. 1. COMPOSITION Method. — Weigh two small pieces of bone. Drop one into HC1 and allow it to remain until the action ceases. Burn a second piece in a crucible. Weigh what remains in both cases. Observations. — 1. What is the original weight of each piece ? 2. What happens when the bone is put in acid ? Its per- centage of loss in weight ? 222 THE HUMAN BODY AS A MACHINE 3. Is the bone now flexible ? 4. What happens when the bone is burned in a crucible ? Percentage of loss ? 5. Is it flexible after burning ? Conclusions. — 1. What substance is taken out by the acid ? By the heat ? 2. What is the purpose of each of these two substances ? Observations. — 1. Note the membrane (periosteum) covering the larger pieces of bone. Is it attached to the bone loosely or closely ? 2. Is it a strong or weak membrane ? Conclusions. — 1. For what does the periosteum seem to be fitted ? 2. The periosteum is a living and growing surface on the live bone ? Would it probably mend a crack or fracture in the bone ? If so, explain. 2. JOINTS Observations. — 1. Study a joint of any skeleton, as a frog's. Move the joint. In how many directions will it move ? 2. Can it be easily twisted or rotated ? 3. Can you tell whether it is hingelike, ball and socket, gliding, or rotary ? 4. Note how the joints are held together by a tough tissue (ligament). Is it tough? Elastic? Strong? Conclusions. — 1. How many different kinds of joints can you find in a skeleton ? 2. How are the bones of the skeleton held together ? Observation. — Can you find where muscles have been at- tached to the bone ? Are the means of attachment (tendons) soft or tough ? Elastic or unyielding ? Conclusion. — Why are muscles attached to bones ? 3. GENERAL SKELETON Observations. — 1. Note that the skeleton is in two general parts, — the axial, of the vertebral column or backbone, and THE HUMAN BODY AS A MACHINE 223 skull ; and the appendicular, of the appendages or parts attached to the main axis. Which part is composed of the greater num- ber of bones ? 2. Note that the spinal column is composed of many single bones (vertebrae). Are they immovable, or flexibly arranged? 3. How many ribs do you find ? Are they all alike ? 4. Where are the ribs fastened ? Conclusions. — 1. What seems to be the uses of the skeleton ? 2. What good purpose in having so many bones in the skeleton ? 3. Why is the axial skeleton made up of so many bones ? 4. Why is the spinal column curved rather than straight ? d. Nervous System Materials. — Demonstration specimens of nervous system of a frog. Observations. — 1. Find the brain of the frog. Note that in front of the brain are two olfactory lobes leading to the nos- trils. Just back of these find enlargements called cerebral hemispheres; just back of these are the optic (sight) lobes or midbrain, followed by a small cerebellum, which in turn is followed by a long portion, the medulla oblongata, which joins imperceptibly with the long dorsal nerve or spinal cord. How far backwards does the spinal cord extend ? 2. Note the many pairs of nerves given off from the brain and spinal cord. Note. — These nerves branch and rebranch into very minute fibers some of which end in the muscles, and are therefore called motor (motion) nerves. Still others pass from the surface of the body inwards. They receive im- pressions as of touch, light, heat, sound, etc., and are called sensory nerves. 3. Compare with the diagram of the nervous system of man. Conclusion. — If a sensory ending is affected by any external stimulus as noted above, where must the message be carried before the muscles may be influenced ? 224 THE HUMAN BODY AS A MACHINE Questions 1. What is the purpose of a nervous system ? 2. What senses do you consider the most important in a frog ? In man ? Why ? 3. Why are the bones in the hind leg of a frog so differ- ently arranged and shaped than the legs of man ? 4. Why cannot a frog jump backwards ? 5. Distinguish between voluntary and involuntary muscles. 6. Why is a slow walk of little value as exercise ? 7. What is the effect of tobacco on muscles ? 8. Why should one who works to excel in athletics abstain from the use of alcohol ? 9. How is bodily heat produced ? 10. Explain how and why the muscles should be exercised. 11. Why do many people have round shoulders ? 12. Why are some forms of exercise better than others ? 13. What is flesh ? 14. Why is exercise in the open air best ? 15. Why is strict training necessary for success in athletics ? 16. What is tetanus ? 17. What is the difference between a break and a sprain ? 18. Explain how to care for broken bones. 19. Why avoid heavy strains on the bones of the young ? 20. How treat a sprain ? A break ? 21. What is the dislocation of a bone ? How treat it ? 22. Show on the arm of another pupil just how you would treat a fracture, pending the arrival of a surgeon. 23. Why are low desks injurious to the young ? 24. Why should deformities be corrected in youth ? 25. How can you tie a knot in a bone ? 26. Why is the shoulder more often dislocated than the hip ? 27. May high pillows be injurious ? How ? 28. Should young children be urged to walk early ? Explain. 29. What is the use of cartilage ? What is marrow ? THE HUMAN BODY AS A MACHINE 225 Special Reports 1. Man as a vertebrate. Comparison with other vertebrates. 2. Massage and its benefits. 3. Methods for developing muscles in the gymnasium. 4. Methods for exercising. 5. Proper care of the muscles. 6. Methods of training for athletic contests. 7. Spasms and how to manage. 8. The care of sprains. References Hunter, Essentials of Biology, Chap. XXIII. Elements of Biology. Chaps. XXXI, XXXII. Hutchison, "Errors in Exercise." Outing Magazine, April, 1910. Davison, The Human Body and Health (Advanced). Chap. XVII. Ritchie, Human Physiology. Chaps. III. IV, V. Hough and Sedgewick, The Human Mechanism. Chap. II. Hutchison, "Athletics and the Heart." Outing Magazine, July, 1910. SHARPE'S LAB. MAN. — 15 FOODS AND DIETARIES PROBLEM XLII A study of food values and diets. Method. — Refer to the tables and Figures in the following pages. a. Food Values and Cost1 (Method I, Portions) COMPARATIVE VALUES AND PRICES OF FOOD MATERIALS 2 (See Summary I for additional data.) 10 CENTS WILL 10 CENTS WILL PURCHASE — PURCHASE — PRICE PRICE KIND OF FOOD PER POUND Fats and KIND OF FOOD PER POUND Fats and Proteid Carbo. Proteid Carbo. (Energy^ (Energy) Beef Cents Pound Calories 3 Beef— Cont. Cents Pound Calories Tenderloin Rump .... 12 .114 920 steak .... 25 .064 415 Shoulder . . . 10 .115 920 Sirloin steak. . 20 .081 520 Second cut Short steak . . 20 .081 520 round . . . 8 .205 745 Loin roast . . 18 .090 580 Neck .... 7 .207 1,100 Rib roast . . . 16 .088 730 Brisket. . . . 6 .200 1,946 First cut round . 16 .130 560 Plate . . . . 6 .230 2,150 Round steak. . 14 .135 635 Flank .... 6 .284 1,860 Chuck .... 12 .129 765 Shank .... 5 .256 1,090 1 Average market in 1902. 10 cents will purchase fully 20 % less to-day. 2 Milner, Reprint from Yearbook, Department of Agriculture, 1902. 3 A calorie is here denned as the amount of heat required to raise one kilo- gram of water (1000 cuhic centimeters) one degree centigrade. 226 FOODS AND DIETARIES 227 KIND OF FOOD PRICE PER POUND 10 CENTS WILL PURCHASE — KIND OF FOOD PRICE PER POUND 10 CENTS WILL PURCHASE — Proteid Fats and Carbo. (Energy) Proteid Fats and Carbo. (Energy) Veal Poultry Cents Pound Calories Cents Pound Calories Cutlets .... 23 .089 310 Turkey . . . 18 .092 600 Loin and rib . . 18 .093 385 Chicken . . . 15 .092 520 Leg . 16 .098 390 Shoulder or TTT* T JTfSn breast . . . 12 .180 530 Chuck and neck 12 .133 425 Salmon, fresh . 35 .040 175 Knuckle or Halibut, smoked 20 .097 475 shank . . . 6 .346 985 Cod, salt, bone- Flank .... 6 .424 1,370 less .... 20 .139 275 Halibut, fresh . 18 .080 265 Salmon, canned 15 .146 615 Mutton and Shad .... 12 .078 315 Lamb Bluefish . . . 12 .083 175 Mackerel, fresh 12 .096 305 Loin 18 .076 810 C*r\r\ frocli 1 O 280 Leg . 14 .107 640 UOQ, iresii . . Mackerel, salt . 8 . .204 £O\J 1,290 Chuck and Cod, salt . . . 9 .211 350 shoulder . . 12 .099 1,120 Lobster, canned 35 .052 175 Neck .... .243 1,970 Oysters, "solids" 181 .030 130 Flank .... 10 .276 3,630 Lobster, fresh 16 .037 90 Clams in shell . (2) .025 79 Pork Miscellaneous Smoked ham . Bacon .... 20 14 .071 .065 840 1,985 Sausage . . . Lard . . . . 10 9 .130 2,125 4,685 Smoked shoul- der . . » ~M 13 .108 1,130 Fresh ham . ; 12 .112 1,120 Dairy Fresh shoulder . 10 .120 1,480 Products, etc. Ribs and loin . 10 .134 1,270 Butter .... 28 .004 1,300 Fat salt pork . . 10 .019 3,670 Eggs (per dozen) 16 .083 400 1 35 cents a quart. 2 40 cents a peck. 228 FOODS AND DIETARIES KIND OF FOOD PRICE PER POUND 10 CENTS WILL PURCHASE — KIND OF FOOD PRICE PER POUND 10 CENTS WILL PURCHASE — Proteid Fats and Carbo. (Energy) Proteid Fats and Carbo. (Energy) Dairy Prod- ucts, etc. — Cents Pound Calories Vegetables — Cents Pound Calories Cont. Cont. Cheese .... 16 .163 1,230 Turnips . . . 1 .090 1,250 Whole milk . . 31 .110 1,080 Skimmed milk . 1.52 .203 1,130 Cereal Cream .... 153 .034 1,220 Products Condensed milk 12 .073 1,260 Crackers . . . 8 .134 2,380 Vegetables Rice 8 .100 2,040 Wheat break- Canned corn . 15 .028 455 fast foods4 7.5 .161 2,260 Canned peas . . 12 .030 215 Oatmeal4 . . . 7.5 .222 2,460 Baked beans, Buckwheat . . 6 .069 2,770 canned . . . 12 .058 500 Barley .... 5 .170 3,300 Canned toma- Hominy . . . 5 .166 3,300 toes .... 6 .020 175 Bread, white . 5 .184 2,430 Celery .... 5 .045 350 Wheat break- Dried beans . . 4 .662 4,010 fast food & . . 4 .302 4,250 Split peas . . . 4 .616 4,400 Oatmeal 5 . . 4 .418 4,625 Green beans . . 3 .136 1,230 Rye flour . . . 3 .227 5,430 Green peas . . 3 .105 850 Wheat flour . . 3 .380 5,490 String beans . . 3 .067 600 Graham flour . 3 .443 5,580 Onions .... 3 .047 685 Entire wheat Squash .... 3 .023 350 flour .... 3 .460 5,580 Pumpkins . . 3 .017 200 Corn meal . . 2.5 .368 6,620 Cauliflower . . 2.5 .043 560 Cabbage . . . 2.5 .056 500 Sweet potatoes . 2 .060 1,900 Sugars, Green corn . . 2 .060 900 Starches, etc. Parsnips . . . 1.5 .069 1,600 Cornstarch . . 8 2,080 Beets . . . . 1.5 .069 1,130 Tapioca . . . 6 2,780 Potatoes . . . 1.5 .120 2,070 Sugar .... 6 3,130 1 6 cents a quart. 4 As put up in packages. 2 3 cents a quart. 5 In bulk. 8 25 cents a quart. FOODS AND DIETARIES 10 CENTS WILL 10 CENTS WILL PURCHASE — PURCHASE — PRICE PRICE KIND OF FOOD PER POUND Fats and KIND OF FOOD PER POUND Fats and Proteid Carbo. Proteid Carbo. (Energy) (Energy) Sugars, Cents Pound Calories Fruits — Cont. Cents Pound Calories Starches, etc. • — Canned peaches 8 .009 280 Cont. Bananas . . . 7 .011 430 Molasses . . . 6 2,580 Oranges . . . 7 .011 345 Olive oil ... 75 565 Berries .... 6 .007 290 Cherries . . . 6 .015 575 Fruits Muskmelon . . 5 .006 180 Figs . 16 .027 930 Cranberries 4 .010 535 Dates .... 10 .019 1,095 Fresh peaches . 4 .025 635 Prunes .... 10 .018 1,190 Pears . . . . 3 .020 980 Raisins .... 10 .023 1,445 Grapes .... 3 .033 1,120 Pineapple . . 10 .004 200 Watermelon . . 3 .006 200 Dried apples . . 10 .016 1,350 Apples .... 1.5 .027 930 Dried apricots . 10 .047 1,290 NOTE. — Grams of proteid or carbohydrates may be reduced to calories by multiplying by 4.1, of fats by 9.3; ounces of proteid and carbohydrate by multiplying by 116, of fats by 264. Observations. — 1. Do foods furnish nutrients in the same proportions ? At the same cost ? Explain. 2. Are the best foods the costliest ? Explain. See Fig- ure 55. 3. 'Are the cheapest foods those that are the least nutri- tious ? Conclusions. — 1. Illustrate what you mean by a cheap food. An expensive one. 2. Show how a food may be an expensive source of proteid, and yet a cheap source of energy. FIG. 55. — Diagram showing the dif- ference in cost of three foods, each of which furnishes about the same amount of nourishment. 230 POODS AND DIETARIES b. Nutritive Values as compared with Cost 1. As SOURCES OF PROTEID (TISSUE BUILDERS) Note. — Foods may be considered as cheap that furnish more than .15 pound of proteid for 10 cents at ordinary prices. Observation. — Refer to the table and list those foods that appear cheap as sources of proteid. Note. — • Foods may be considered as medium-priced that fur- nish from .075 to .15 pound of proteid for 10 cents at ordinary prices. Observation. — Write out a list of the medium-priced sources of proteid as given in the table. Note. — Foods are considered as expensive if they furnish less than .075 pound of proteid for 10 cents at ordinary prices. Observation. — Kefer to the table and list the foods given that are considered expensive sources of proteid. 2. As SOURCES OF ENERGY, OR FUEL Note. — Foods may be considered as cheap if they furnish more than 1900 units of energy for 10 cents at ordinary prices. Observation. — List as many cheap energy producers as you can. Note. — Foods may be considered as medium-priced if they furnish from 800 to 1900 units of energy for 10 cents at ordinary prices. Observation. — What foods fulfill the requirements for being medium-priced ? Note. — Those foods furnishing less than 800 units of energy for 10 cents may be considered as expensive energy producers. Conclusions. — 1. What foods are cheap both as proteid pro- ducers and as energy producers ? 2. What foods are expensive both as energy producers and as proteid producers ? FOODS AND DIETARIES 231 Some foods that are otherwise expensive may some- times be justifiable for the sake of variety, and to please the palate, or as appetizers. Can you name any such ? 3. What are the condiments ? What is their function ? 4. What are stimulants ? Flavors ? What are their func- tions ? c. The Family Dietary 1. DAILY CALORIE NEEDS (APPROXIMATELY) Observations : — 1. For child under 2 years 900 calories. 2. For child from 2 to 5 years 1200 calories. 3. For child from 6 to 9 years 1500 calories. 4. For child from 10 to 12 years 1800 calories. 5. For girl from 12 to 14 years (woman, light work, also) 2100 calories. 6. For boy from 12 to 14, girl from 14 to 16 (man, sedentary) 2400 calories. 7. For boy from 15 to 16 years (man, light muscular work) 2700 calories. 8. For man (moderately active muscular work) 3000 l calories. 9. For farmer (busy season) . . . 3200 to 4000 calories. 10. For ditchers, excavators, etc. . . 4000 to 5000 calories. 11. Lumbermen, etc 5000 and more calories. Note. — An average result for light work may also be ob- tained by multiplying the body weight in pounds by 16.1 calories. Conclusions. — 1. Refer to the above table and determine approximately your own daily calorie needs. 2. Determine the daily calorie needs for your own family. 2. DAILY DIETARY Observation. — Dr. R. H. Chittenden2 of Yale University concludes that we need proteids, fats, and carbohydrates in about 1 Chittenden also gives 60 grams of proteid to 2700 calories of energy. 2 Atwater gives ratios of 1.4 proteid to 3.4 fat to 5.2 carbohydrate. Voit gives 2.5 proteid to 2 fat to 5. 5 carbohydrate and is considered authoritative by many. 232 FOODS AND DIETARIES the ideal ratio of 1 to 3 to 6. How many calories of each in every 100 ? Dr. Irving Fisher of Yale University has worked out tables of what is known as the 100 calorie portion, mentioned in the following tables. Refer to Dr. Fisher's tables and fill in the values for your own daily dietary after the following model. (a) Sample Day's Dietary TOTAL CALOEIES CALORIES FROM MARKET PRICE COM- PUTED PRICE FOR 'ROTEID CALO- RIES FOR TEN CENTS Proteid Fat Car- bohy- drates Breakfast 1 shredded wheat bis- cuit yields .... 100 13 4.5 82.5 1 slice of bread yields 100 13 6 81 1 serving of apple sauce yields 100 2 5 93 1 small square of butter yields 100 .5 99.5 0 £ cup of cream yields 100 5 86 9 Calories from break- fast 500 33.5 201 265.5 Dinner 1 large serving boiled beef, lean, yields . . 100 90 10 0 1 good-sized baked po- tato yields .... 100 11 1 88 1 serving of spinach yields 50 7.5 33 9.5 2 pats of butter yield 200 1 199 0 2 slices of bread yield 200 26 12 162 2 small servings cream rice pudding yield . 200 16 26 158 Calories from din- ner . 850 151.5 281 417.5 FOODS AND DIETARIES 233 TOTAL CALORIES CALORIES FROM MARKET PRICE COM- PUTED PRICE FOR PBOTEID CALO- RIES FOR TEN CENTS Proteid Fat Car- bohy- drates Supper 3 slices of bread yield 300 2 small glasses of milk yield . • . 200 39 38 5 6 18 104 86 0 243 58 9 194 i glass of cream yields 100 6 prunes yield ... 200 Calories from sup- per 800 88 208 405 Day's total, calo- ries 2150 The day's total dietary has furnished 2150 calories. Assum- ing the body weight to be 140 pounds, and the day's work to be light, the calculated food need, 140 times 16.1 calories, or 2254 calories, is found to correspond closely to the actual amount required, as given on page 231. Name Daily calorie needs . Amount computed- Discrepancy Age Weight. .Ibs. Conclusions. — 1. How does the day's total of calories used compare with that given in the table of daily needs for a person of your age ? 2. If there is any discrepancy, how can you account for it? 3. How much proteid furnished for 10 cents? How many units energy ? 4. Is your listed diet cheap, medium-priced, or expensive ? Reasons ? 5. Can you suggest where it might be improved ? 234 FOODS AND DIETARIES 6. Try forming a diet giving least quantities of nutrients so that they total your daily calorie needs. Observation. Home Work. — Fill out a similar table for your family dietary for one or more days. Lump the portions used at a meal, and figure out the data for the rest of the tabulation. (The average for one week would be best.) Conclusions. — 1. Is your family dietary cheap, medium- priced, or expensive? Reasons? (Answer as proteid pro- ducer and energy producer.) . 2. Can you suggest how it might be improved ? Explain. 3.1 Would your family be content to use more milk and eggs, and meat not more than once a day ? Which would be the cheaper ? (6) Table o/lOO Food Units2 NAME OF FOOD PORTION CONTAIN- ING 100 FOOD UNITS (APPEOX.) WT. OF 100 CALO- RIES (oz.) CALORIES FURNISHED BY Pro- teid Fat Car- bohy- drates Cooked Meats Beef, round, boiled (fat) . . . Beef, round, boiled (lean) . . . Beef, round, boiled (med.) . . . Beef, 5th rib, roasted .... Beef, 5th rib, roasted .... Beef, 5th rib, roasted .... Beef ribs boiled Small serving . . Large serving . . Small serving . . Half serving . . Small serving . . Very sm. serving Small serving . . Very sm. serving 1.3 2.2 1.6 .65 1.2 .88 1.1 .87 4 .96 .96 1.8 40 90 60 12 25 18 27 21 19 23 24 40 60 10 40 88 75 82 73 79 0 77 76 60 0 0 0 0 0 0 0 0 81 0 0 0 Beef, ribs, boiled Calf 's-foot jelly . .... Chicken canned One thin slice . . One small chop . Ord. serving . . Lamb chops, boiled, av. . . . Lamb, leg, roasted 1 Much excess of proteid (as from lean meats, etc.) is to be avoided, as it is by far the most expensive nutrient, and besides being a costly waste may re- sult in bodily disorder. 2 These tables are here given by courtesy of The Journal of the American Medical Association, Vol. XLVIII, No. 16 ; they were compiled by Dr. Irving Fisher, Yale University. FOODS AND DIETARIES 235 PORTION CONTAIN- WT. OF 100 CALO- C FUB ALOB NI8HI IBS D BY (APPBOX.) BIES (oz.) Pro- teid Fat Car- bohy- drates Cooked Meats — Cont. Mutton leg boiled Large serving . . 1 2 35 65 o Pork, hain, boiled (fat) .... Pork ham boiled Small serving . . Ord serving .73 1 1 14 28 86 72 0 o Pork, ham, roasted (fat) . . . Pork, ham, roasted (lean) . . . Turkey as purchased canned . . Veal leg, boiled Small serving . . Small serving . . Small serving . . Large serving . .96 1.2 .99 24 19 33 23 73 81 67 77 97 0 0 0 o Uncooked Meats, Edible Portion Ord serving 1.8 40 60 o Beef loin av (fat) Small servin0" . 1 i 22 78 o Beef, loin, porterhouse steak, av. Beef, loin, sirloin steak, av. . . Beef ribs lean av . Small steak . . Small steak . . Ord serving 1.3 1.4 1 8 32 31 4? 68 69 58 0 0 o Beef, round, lean av Ord serving . 2.2 54 46 o Ord. serving . . 2.2 47 53 o Beef juice . . 14 78 99 o Chickens (broilers) av Clams, round in shell, av. . . . Cod (whole) Large serving . . 12 to 16 . . . . Two servings • 3.2 7.4 49 79 56 95 21 8 5 0 36 o Goose (young) av. Half serving . .88 16 84 o Halibut steaks, av Ord. serving . . 2.8 61 39 o Liver (veal) av Two sm. servings 2.8 61 39 o Lobster (whole) , av Two servings . 4.1 78 90 2 Mackerel (Span.), whole, av. . . Mutton, leg, hind, lean, av. . . Oyster in shell av Ord. serving . . Ord. serving . . One dozen 2 1.8 6 8 50 41 49 50 59 22 0 0 29 Pork, loin, chops, av Pork, ham, lean, av Very sm. serving Small serving . . .97 13 18 99 82 71 0 0 Pork, bacon, med. fat, av. . . Salmon (Cal.), av Small serving . . Small serving . .53 1.5 6 30 94 70 0 0 Shad, whole av. . . Ord serving 2.1 46 54 o Trout, brook, whole, av. . . . Turkey, av Two sm. servings Two sm. servings 3.6 1.2 80 9q 20 71 0 o Vegetables 15 14 0 86 Asparagus, av., canned . . . 19 33 5 62 Asparagus, av., cooked . . 7 19 18 63 19 236 FOODS AND DIETARIES NAME OP FOOD PORTION CONTAIN- ING 100 FOOD UNITS (APPKOX.) Wr. OF 100 CALO- RIES (oz.) CALORIES FURNISHED BY Pro- teid Eat Car- bohy- drates Vegetables — Cont, Beans, baked, canned .... Beans, lima, canned .... Beans, string, cooked .... Beets, edible portion, cooked Small side dish . Large side dish . Five servings . . Three servings . 2.66 4/44 16.66 8.7 11 7.6 5.81 11 19 3.5 20 12 3.15 18 7.6 7.1 8.4 5.3 5.84 6.3 3 3.05 3.62 3.14 3.57 .6 1.7 13 17 15 6.1 7.4 3.5 15 15.2 8.7 9.62 21 21 15 2 20 10 10 23 24 13 18 17 27 25 31 13 12 10 10 25 23 11 11 10 11 4 6 15 18 10 15 12 15 15 21 13 10 18 4 48 23 8 8 34 15 5 10 10 10 1 14 8 5 40 7 34 3 27 1 1 25 1 63 9 4 3 27 66 10 9 16 7 4 51 61 75 37 75 72 82 56 62 71 77 72 73 72 61 61 82 48 83 56 72 50 88 88 65 88 33 85 81 79 63 19 78 76 69 72 83 39 Carrots, edible portion, fresh Carrots cooked Two servings . . Cauliflower as purchased Celery edible portion One side dish . . Cucumbers edible portion . . Lentils cooked . Mushrooms as purchased Onions cooked Two 1'ge servings One one half serv. Parsnips, edible portion . . . Parsnips cooked Peas green canned . . Two servings . . One serving . . One good-sized . One large-sized . One serving . . One serving . . One half serving . Half av. potato . Peas, green, cooked Potatoes baked Potatoes, boiled Potatoes, mashed (creamed) . . Potatoes steamed . . Potatoes chips Potatoes, sweet, cooked . . . Pumpkins edible portion Radishes, as purchased Rhubarb edible portion Spinach cooked Two ord. servings Squash edible portion Succotash, canned Ord. serving . . Four av. servings Tomatoes, fresh, as purchased . Tomatoes canned Turnips, edible portion . . . Vegetable oysters Two 1'ge servings FOODS AND DIETARIES 237 NAME OP FOOD PORTION CONTAIN- ING 100 FOOD UNITS (APPBOX.) WT. OF 100 CALO- RIES (oz.) ' CALORIES FURNISHED BY Pro- teid Fat Car- bohy- drates Fruits (Dried) Apples as purchased . . . 1.2 1.24 .99 1.1 1.1 1.14 1.35 1 1.1 7.3 3.3 3.9 5.92 4.61 3.5 5.9 4.6 5.8 8.6 4.4 7.5 4.8 7.57 4.2 9.2 7.57 8.77 5.18 1.31 9.4 6.62 10 4.78 4.80 5.40 3.98 3 7 2 2 5 3 3 3 3 3 2 2 8 6 5 9 3 4 6 5 3 5 7 0 5 9 0 4 2 6 0 7 4 0 4 3 7 3 7 7 0 0 0 9 9 7 5 5 0 0 5 16 8 9 0 10 12 15 4 0 0 14 0 0 91 3 0 2 2 0 7 4 90 90 91 91 95 97 97 88 88 90 93 93 92 94 90 75 89 87 94 85 85 80 89 100 95 77 100 96 7 91 100 91 94 100 89 93 Apricots as purchased .... Dates, edible portion .... Dates as purchased Three large . . One large ... Three large ... _. Prunes, edible portion .... Prunes, as purchased . . . Raisins as purchased . . Fruits (Fresh or Cooked) Apples, as purchased Two apples . . Apples, sauce . Ord. serving . . Apricots, edible portion . . Apricots cooked Large serving One large . . . Bananas, edible portion . . . Blueberries Blueberries, canned Half ord. serving Cherries, edible portion . . Cranberries, as purchased . . . Nectarines Olives ripe About seven . . One very large . Large glass • . . Three ordinary . Ord. serving . . Ord. glass . One large . . . Oranges, as purchased, av. . . . Peaches, as purchased, av. . . . Peaches, juice Pears . . Pears, sauce 238 FOODS AND DIETARIES NAME OF FOOD PORTION CONTAIN- ING 100 FOOD UNITS (APPBOX.) WT. OF 100 CALO- RIES (oz.) CALORIES FURNISHED BY Pro- teid Fat Car- bohy- drates Fruits (Fresh or Cooked) — Cont. Pineapples, edible portion, av. . 8 5.18 6.29 9.1 27 .44 9.7 .77 3.12 .82 1.05 .8 .72 1.7 6.7 1.06 2.05 9.4 4.9 13 .98 .96 .89 2.51 4.29 2.45 .8 .95 .82 1.3 1.1 1.9 1.35 4 10 8 10 6 .5 34 25 76 25 22 25 25 5 21 10 24 37 19 15 7 6 7 19 26 9 6 10 6 5 5 9 6 6 14 0 15 6 99.5 12 73 8 73 76 74 73 86 37 23 50 7 52 10 22 23 25 10 56 12 45 12 33 32 32 32 36 90 76 92 75 88 0 54 2 16 2 2 1 2 9 42 67 26 56 29 75 71 71 68 71 18 79 49 78 61 63 63 59 58 Raspberries, black Raspberries, red Two servings . . Watermelon, av Dairy Products Butter, ordinary pat .... Buttermilk . . Ipat .... 1J glasses . . . 12 cubic in. . . 4 cubic in. . . . lz cubic in. . . lz cubic in. . . lz cubic in. . . lz cubic in. . i ord. glass . . Cheese, Am. pale .... Cheese, cottage Cheese, full cream Cheese, Neufchatel .... Cheese Swiss • . Cheese, pineapple Cream Kumyss Milk, condensed, unsweetened . Milk, skimmed lz glass .... Small glass . . Two glasses . . z ord. sq. piece $ ord. sq. piece Small piece . . . Milk whole Whey Cakes, Pastry, Puddings, and Desserts Cake, chocolate layer .... Cake, gingerbread Cake sponge . Custard, caramel Custard, milk . Ord. cup . . . Two thirds ord. . Half a doughnut Custard, tapioca Doughnuts . . ... . Macaroons Pie apple One third piece . One fourth piece One third piece . One third piece . Pie, cream Pie, custard .... Pie, lemon FOODS AND DIETARIES 239 NAME OF FOOD PORTION CONTAIN- ING 100 FOOD UNITS (APPBOX.) WT. OF 100 CALO- RIES (oz.) CALORIES FURNISHED BY Pro- teid Fat Car- bohy- drates Cakes, Pastry, Puddings, and Desserts — Cont. One fourth piece One third piece . 1.2 1.9 3.02 2 2.65 2 2.8 3.85 6 1.05 1 1.2 1.1 1.3 14.6 .86 1.03 1.2 .53 .52 .49 .50 .57 1.4 .48 .47 .62 .46 .56 .48 1.5 8 10 6 7 8 12 1 1 10 1 .5 .5 1 2 18 0 0 0 13 13 10 16 4 10 9 9 20 6 22 10 9 38 42 3 12 13 25 1 1 3 0 2.5 0 84 91 15 0 0 0 77 79 86 82 77 20 84 85 63 87 74 83 7 54 48 91 81 79 63 98 98 87 99 97 99.5 15 7 67, 100 100 100 10 8 4 2 10 70 7 6 17 7 4 7 84 Pie squash Pudding, brown betty .... Pudding, cream rice .... Pudding, Indian meal .... Pudding, apple tapioca . . . Tapioca cooked Half ord. serving Very small serving Half ord. serving Small serving Ord. serving . . Sweets and Pickles Four teaspoons . Olives, green, edible portion . . Olives, ripe, edible portion . . Seven olives . . Seven olives . . Sugar granulated Three teaspoons or 1? lumps . . . Four teaspoons . Four teaspoons . Eight to fifteen . Syrup maple . Nuts, Edible Portion Almonds, av Brazil nuts Three ord. size . Coconuts Chestnuts, fresh, av Filberts av. Ten nuts . . . Hickory nuts Peanuts . Thirteen, double About eight . . About eighty . . About six . . . Ord. thick slice . Pecans, polished ...... Pine nuts (pignolias) .... Walnuts, California Cereals Bread brown av. . . . 240 FOODS AND DIETARIES NAME OK FOOD PORTION CONTAIN- ING 100 FOOD UNITS (APPROX.) WT. OF 100 CALO- KIE8 (oz.) CALORIES FURNISHED BY Pro- teid Fat Car- bohy- drates Cereals — Cont, Bread, corn (johnnycake) , av. . Bread, white, homemade . . . Corn flakes, toasted Small square . . Ord. thick slice . Ord. cereal dish . 1.3 1.3 .97 .96 .92 .82 .81 4.2 .96 3.85 5.6 .86 .98 3.1 .94 1.2 .94 .97 .96 . .96 .97 .81 2.1 6.4 .94 3.3 13 5.4 6.3 29 8.25 .56 .69 1.6 12 13 11 10 9 9 11 11 15 14 18 11 9 10 8 12 13 12 15 15 12 9 32 100 17 34 69 20 16 85 17 8 17 5 16 6 1 5 11 20 24 2 2 15 7 11 1 1 1 7 4.5 1 5 5 3 21 68 0 83 60 14 10 47 0 18 72 53 62 72 81 88 85 80 71 65 87 83 71 75 78 90 89 91 81 82.5 87 80 80 85 70 0 0 0 6 17 80 37 15 65 20 30 33 Crackers graham Two crackers Two crackers Large serving Crackers oatmeal Hominy, cooked Ord. serving . . Is serving . . ' . Oatmeal boiled Popcorn Rice, uncooked Rice boiled ... Ord. cereal dish . Ord. cereal dish . One large roll One biscuit . . Rice, flakes Rolls Vienna av Shredded wheat \Vheat flour graham av Wheat flour, patent, family, and straight, grade, spring wheat, Zwieback Size of thick slice of bread . . . One large egg . Miscellaneous Eggs hen's boiled Eggs hen's, whites Eggs hen's yolks Two yolks . . . Omelet Soup bean av .... Very large plate . Two plates . . . Soup, cream of celery .... Consomme . . Two plates . . . Half a square . . Chocolate bitter FOODS AND DIETARIES 241 Note. — Should one desire to add further items to the above table, ob- tain Bulletin 28, U. 6. Department of Agriculture, " The Chemical Com- position of American Food Materials," by Atwater and Bryant. (Send 5 cents in coin to Superintendent of Documents, Washington, D.C.) The weight in ounces of a standard portion equals 1600 divided by number of calories per pound given in table. The calories furnished by proteid equal the percentage of proteid given in the Bulletin table multiplied by 1860 and divided by the number of calories per pound. The same calculation and factor applies to carbohydrates. For fat, calculate the same way, but use the factor 4220 in place of 1860. Verify the three results by add- ing to see if they equal 100 calories. d. Food Values (Method II, Graphic) Observations. — 1. The threefold constitution of any partic- ular food may be represented graphically by the position of a point 0 in a triangle CPF (Fig. 56). Thus the pcint O, representing milk, is located at a height above CF, 19% of the total height of P} which shows that 19% of the food value of milk is proteid ; and at a distance to the right of CP towards F, 52% of the distance, signifying that 52 % of the food value of milk is fat. Where would you locate the point 0 for a *0 JO 70 80 90 100 Fia. 56. — Food map. Composition of milk represented by the point 0. (After Fisher.) food which was 90% proteid? 90% fat? Conclusions. — 1. Ex- plain how P might be called the proteid corner, F the fat corner, and O the carbohy- drate corner. 2. On what line would a food devoid of proteid be located ? If devoid of fat ? SHARPE'S LAB. MAN. — 16 242 FOODS AND DIETARIES Observations. — 1. Two or more foods may be plotted as follows : The combination, if equal in calorie value, is rep- resented by a point midway between them. If the portions are unequal, the point 0 will of course be proportionally nearer the point locating the larger portion. Like- wise, when three foods are combined, the point is first located for two, then this with the third, this with the fourth, etc. Thus in Figure 57 we have three points repre- senting respectively 300, 400, and 500 calories of three separate foods. We first join any two points as 300 and 400, and find their combina- FIG. 57. -Food map. Showing method of tion of 7QQ calories at combining three or more foods. (After . . . Fisher) the point 700 which divides the line joining the 300 and 400, as 3 to 4 and nearer the 400. We now unite this with the 500 and find a new result at the point 1200. It is now evident any number of portions may be thus combined, the final number obtained equaling the sum of the portions, and its location representing its value as a food. What is the percentage composition of the combination of foods represented by the figure 1200 ? Note. — If the lines OF and CP are used to compute the percentage of proteid and fat, how can you get the percentage of carbohydrate ? 2. Professor Chittenden believes that, of each 100 calories used, 10 should be proteid, 30 should be fat, and 60 carbo- hydrate. Locate this combination on a food map. Does it fall within the rectangle wxyz, in Figure 58? Note. — The rectangle wxyz is known as the normal rectangle, and shows FOODS AND DIETARIES 243 where the point 0 of a well-balanced food or combination of foods would be approximately located. Locate other ratios (see note 2, page 231). Conclusions. — 1. Are the following menus poor or well balanced? Note. — See that the value of each is p approximately 900 calories. _\ Why? 1Menu I. — Eggs. Bread and butter. Menu II. — Baked beans. Brown bread. Apple sauce. Menu III. — Oatmeal. Milk and sugar. Fruit. C 10 2« 30 40 50 60 70 80 90 FIG. 58. —Food map. Showing " Normal Rectangle," wxyz. Chittenden's stand- ard of well-balanced ration. (After Fisher.) Menu IV. — Cream soup. Menu V. — Pot roast with rice. Bread and butter. Baked apples. Potatoes. Cabbage. Baked apples and cream. 2. Is the following menu well or poorly planned? Show how you obtain your answer. Menu VI. — Eggs (4 large). Mashed potatoes (2 servings). Baked sweet potatoes (1 large). Custard pie (^ piece). 1 Use the number of portions of each article of the menus you think would best suit your appetite, only seeing that the total is 900 calories. 244 FOODS AND DIETARIES 3. Study the following menu and answer the following questions. Menu VII. — Crackers (4 large). Lettuce (18 oz.). Oysters (4 doz.). Oranges (2 large). (1) What is its nutritive value in proteid? In calories? (2) What is its cost? Is it cheap or expensive? (3) Is it well balanced? 4. Calculate the amount of proteid, carbohydrates, and fat in your own diet for one day. What is its cost ? Is it well balanced ? EXTRA MENUS TO MAP Menu X. — Bread. Cheese. Onions. Menu XI. — Eggs. Menu VIII. — Whole wheat bread. Whole milk. Prunes. Menu IX. — Oatmeal with sugar and cream. Apricots. Mashed potatoes. Macaroni. Bread and butter. Bread pudding. 1. Questions What is meant by a balanced diet ? 2. What is a daily ration for an adult ? 3. What are the uses of the nutrients of foods ? 4. What are the reasons for cooking foods ? 5. What are some of the causes of constipation ? 6. What is a food unit ? 7. How is the normal rectangle located on a food map? Construct one, using Chittenden's ratios. Atwater's ratios. Voit's ratios. 8. What is the necessity for a mixed diet ? 9. Name some common errors in diet. FOODS AND DIETARIES 245 10. What is the value of soups as foods ? 11. What is a fireless cooker ? What is its main value ? 12. How does milk compare with eggs in food value ? 13. How do nuts compare with meat as a source of proteid ? Which is the cheaper ? 14. Discuss the subject of poultry as food, — its value, cost, etc. 15. Explain how beans and peas may well be called " the lean meat of the vegetable kingdom." 16. How does rice compare with wheat as a food ? 17. What are the condiments and flavors ? What is their use? 18. Of what importance is diet in sickness ? 19. Why do Arctic-living tribes live almost exclusively on blubber, or fat ? 20. What are the uses of inorganic foods ? 21. What is known about alcohol as a food ? Nicotine ? 22. How does ten cents' worth of beans compare in food value with ten cents' worth of lobster ? 23. How do animal foods compare in cost with vegetable foods ? 24. How does milk at 6 cents per quart compare in value with rump beef at 14 cents per pound ? 25. What is the principal reason for using butter on bread ? 26. How does cheese at 16 cents per pound compare in economy with meat at the same price ? 27. Is it necessary that eggs be perfectly fresh and not case eggs in order to be wholesome ? 28. What are the principal reasons for using fruit in the diet? 29. Are soup greens economical ? What might be used in their place ? 30. Which is most economical as a source of fat, — lard, suet, or butter ? 246 FOODS AND DIETARIES Special Reports 1. The necessity for a mixed diet. 2. Common errors in diet. 3. Proper methods in cooking foods. 4. Work of the United States government in determining the nutri- tive value of foods. 5. The value of eggs as food. 6. Some foods that would make a satisfactory dinner at small cost. 7. The use of milk as food. 8. The use of soups as food. 9. Some commonly used expensive foods and how to get along with- out them. 10. The necessity for food. 11. The comparative cost and value of corn meal, sirloin steak, cod- fish, and oysters as food. 12. Show how 10 cents' worth of corn meal will equal $2 worth of oysters. How 10 cents' worth of stewing beef is equal in value to 25 cents' worth of sirloin. 13. The value of peas, beans, and other legumes as food. 14. Fish as food. 15. The composition and cooking of meats. 16. How to live on a small income. 17. The use of the microscope in food adulteration. 18. The fireless cooker and its uses. 19. Poultry as food. 20. Human foods and their nutritive value. 21. Sugar as food. 22. The preparation of vegetables for the table. 23. Practical sanitary and economic cooking. 24. Nutritive value and costs of foods. 25. Try expanding the following paragraphs as special reports. (Choose one.)- a. "The ideal diet is that combination of foods which, while imposing the least burden on the body, supplies it with exactly sufficient material to meet its wants." b. " Too much food is as bad as too little and occasions a waste of energy and strength in the body as well as a waste of nutritive material." c. "In ordinary mixed diet the chief sources of proteid are meat, fish, and milk among animal foods, and the cereals and legumes among vegetable foods. Beans, peas, and oatmeal are rich in proteid and hence especially valuable foods. About nine tenths of the fat in the ordinary FOODS AND DIETARIES 247 diet is obtained from the animal foods, while the vegetable foods furnish approximately nine tenths of the carbohydrates." d. " The common or average American family wastes as much food as a French family would live upon.' ' e. " We live not upon what we eat, but upon what we digest." /. "As many lives are cut short by unhealthful food and diet as through strong drink." References J Hunter, Essentials of Biology. Chap. XXIV. Davison, The Human Body and Health (Intermediate). " Foods, Nutritive Value and Cost." Farmers' Bulletin No. 23, U. S. Department of Agriculture. Abel, Practical Sanitary and Economic Cooking. Public Health As- sociation. Abel, " Beans, Peas, and Other Legumes as Food." Bulletin No. 121, U. S. Department of Agriculture. " Cereal Breakfast Foods." Farmers' Bulletin No. 249, U. S. Depart- ment of Agriculture. "Eggs and their Uses as Food." Farmers' Bulletin No. 128, U. S. Department of Agriculture, 1906. • "Fish as Food." Farmers' Bulletin No. 85, U. S. Department of Agriculture, 1907. ** The Composition and Cooking of Meats." Farmers' Bulletin No. 34, U. S. Department of Agriculture, 1904. "Milk as Food." Farmers' Bulletin No. 74, U. S. Department of Agriculture, 1904. "Facts about Milk." Farmers' Bulletin No. 42, U. S Department of Agriculture, 1906. "Poultry as Food." Farmers' Bulletin No. 182, U. S. Department of Agriculture, 1903. Snyder, Harry, Human Foods and Their Nutritive Value. "Sugar as Food." Farmers' Bulletin No. 93, U. S. Department of Agriculture, 1906. "The Preparation of Vegetables for the Table." Farmers' Bulletin No. 256, U. S. Department of Agriculture, 1906. "Nuts and their Use as Food." Farmers' Bulletin No. 132, U. S. Department of Agriculture. Hogan, Children's Diet in Home and School. 1 Address Department of Home Economics, Ithaca, N.Y. for further infor- mation, or the American School of Home Economics, 600 W. 69th St., Chicago, 111. 248 FOODS AND DIETARIES " Corn and Corn Products." Farmers1 Bulletin No. 298, U. S. Depart- ment of Agriculture. Atwater, Dietaries in Public Institutions. Reprint from Yearbook 1901. Langworthy, "Functions and Uses of Food." Experiment Station Circular 46. "Potatoes and Other Root Crops as Food." Farmers' Bulletin No. 295, U. S. Department of Agriculture. " Fruit and its Uses as Food." Yearbook Reprint. Davenport, E. C., " Why Food is Costly." Good Housekeeping Maga- zine, April, 1910. "Human Nutrition." Parts I and II, Cornell University Reading Course. Ithaca, N.Y., 1909. Norton, Alice P., Food and Dietetics. American School of Home Economics, Chicago, 1907. Langworthy and Hunt, "Economical Use of Meats in the Home." Bulletin 391 , U. S. Department of Agriculture, 1910. Hendrick, Burton J., "Some Modern Ideas on Food." McClure's Magazine, April, 1910. Chittenden, R. H., The Nutrition of Man. " Economy in Diet." The Independent, March 17, 1910, p. 556. Fisher, Irving, "Dietary Studies." Journal American Medical Asso- ciation, Vol. XLVIII, No. 16. Milner, R. D., "The Cost of Food as related to its Nutritive Value." Reprint from Yearbook, U. S. Department of Agriculture, 1902. Pope and Carpenter, Essentials of Dietetics. Mitchell, Margaret C., "A Course in Cereal Foods and their Prepara- tion." Bulletin No. 200, Agricultural Experiment Station, Washington, D.C. "Report of the President's Home Commission." Senate Document 644, 60th Congress, 2d Session. Journal of Home Economics. Address Benjamin R. Andrews, 525 W. 120th St., New York City. The Household Economist. Davis-Gibbs Co., Springfield, Mass., 1909. Hewett, How to live on a Small Income. Reeve, Energy, Work, Heat, and Transformations. Atwater, " Principles of Nutrition, and Nutritive Value of Food." Farmers' Bulletin No. 142, U. S. Department of Agriculture, 1906. Atwater and Bryant, " The Chemical Composition of American Food Materials." Bulletin 28 (Revised Ed.), U. S. Department of Agri- culture, 1906. McGill, " Infants' and Invalids' Foods." Inland Revenue Department, Ottawa, Bulletin 185, February, 1910, FOODS AND DIETARIES 249 " Retail Prices of Food, 1890-1907." Bulletin U. S. Bureau of Labor, No. 77, 1908, Washington, D.C. • "Nuts as Food." Farmers' Bulletin No. 390, U. S. Department of Agriculture. "Renovated Butter." Farmers' Bulletin No. 424, U. S. Department of Agriculture. "Canned Fruits, Preserves, and Jellies." Farmers' Bulletin No. 203, U. S. Department of Agriculture. " Bread and the Principles of Bread Making." Farmers' Bulletin No. 112, U. S. Department of Agriculture. "Protection of Food Products from Injurious Temperatures." Farm- ers' Bulletin No. 125, U. S. Department of Agriculture. James, Catering for Two. Shafer, John, "The Waste of Overeating." Success Magazine, March, 1910. Rensselaer, M. V., "Food for the Farmers' Family." Cornell Uni- versity Reading Course, Series III, No. 14, 1905. Fisher, Irving, "Food Values." Bulletin 13, American School of Home Economics, Chicago. At water, Helen W., " Bread and Bread Making." Farmers' Bulletin No. 389, U. S. Department of Agriculture. Abel, " The Care of Food in the Home." Farmers' Bulletin 375, U. S. Department of Agriculture, 1909. Benson, "Facts about the Food Problem." Pearson's Magazine, April, 1910. Benton, Living on a Little. Benedict and Carpenter, Eespiratory Calorimeters, etc. Carnegie Institute at Washington, 1910. Brewster, " Meat as a Food." Metropolitan Magazine, April, 1910. Crich ton-Brown, Parsimony in Nutrition. Green, Olive, Everyday Dinners. Hunt, Caroline, " The Daily Meals of School Children." Bulletin 3, U. S. Bureau of Education, 1909. Mitchell, The Fireless Cook Book. Milner, R. D., "The Use of Milk as Food." Farmers' Bulletin No. 363, U. S. Department of Agriculture. Osborne, The Vegetable Proteins. Bevier and Van Meter, Selection and Preparation of Food. Text- book for First Year College Students, American School of Home Economics, 1909. "Food and Diet in the United States." Reprint from Yearbook, U. S. Department of Agriculture. 250 FOODS AND DIETARIES Benson, A. L., "How Food Prices are Made." Pearson's Magazine, May, 1910. Brown, Goodwin, Scientific Nutrition Simplified. Terrill, B. M., Household Management. American School of Home Economics, Chicago, 1907. Richardson, B., The Woman who Spends, a Study of Her Economic Function. SUMMARY I A summary of some food values? DIETARY CALCULATION WITH FOOD VALUES IN CALORIES PER OUNCE BREAKFAST PROTEINS FATS CARBOHYDRATES TOTAL Gluten Gruel, 5 oz. . . . 23.5 1 30 Soft-boiled Egg .... 26.3 41.9 Malt Honey, 1 oz. . . . 86.2 Creamed Potatoes, 5 oz. . 15 40 104 Zwieback, 2 oz 22.8 52.8 171.6 Pecans, f oz 8.4 141 13.4 Apple 5 oz 2 5 6 5 83 98.5 283.2 488.2 869.9 DIETARY CALCULATION WITH FOOD SERVED IN 100 CALORIES PORTIONS DINNER PORTIONS INSERTING PROTEIDS FAT CARBO- HYDRATES TOTAL Nut French Soup . 1 10 20 20 Nuttolene Sauce . 1 29 55 16 Macaroni, Egg . . 1 15 59 26 Baked Potato . . 2 22 2 176 Cream Gravy . . i 5 33 12 Granose Biscuit 11 20 2 128 Butter .... 1 1 99 Malt Honey . . 2 200 Celery .... \ 4 21 Apple Juice . . . i 50 101 106 270 649 1,025 1 Courtesy of American School of Home Economics, Chicago. FOODS AND DIETARIES 251 HOURLY OUTGO IN HEAT AND ENERGY FROM THE HUMAN BODY AS DETERMINED IN THE RESPIRATION CALORIMETER BY THE UNITED STATES DEPARTMENT OF AGRICULTURE. Average (154 Ibs.) CALORIES Man at rest (asleep) .......... 65 Sitting up (awake) 100 Light exercise ..••'.-'. 170 Moderate exercise 190 Severe exercise 450 Very severe exercise 600 PROBLEM XLIII A study of some forms of food adulteration, and some simple means of detecting them. a. Definition Note. — Foods are said to be adulterated when any substance is added to them which does not properly form a part of the food. Such foods are not necessarily unwholesome. This study was first taken up in this country in 1881. The first food inspection law was enacted here in 1883, in Massa- chusetts. More than twenty-five states are now attempting to regulate the character and quality of foods sold in the market. Note. — Starch is sometimes added to sausage to increase its weight, or permit of a larger amount of water or fat meat. If sold as pure sausage, it would clearly not be in any sense poisonous, but should be labeled " misbranded," and is evi- dently a fraud. Why ? b. Chemical Preservation Note. — Such substances as benzoic and boric acids, borax, formaldehyde, and sulphurous acid are used. (Show speci- mens.) c. Coloring Matter 1. Used in cheaper grades of jellies, to imitate good grades; therefore a fraud. 2. Used in tomato catsup, and canned tomatoes. 3. Used to make cucumber pickles greener (copper). 252 POODS AND DIETARIES 4. Used to make peas and beans greener (copper). 5. Used to color poor butter. 6. Added to chopped meats, sausage, etc., to give fresh color. d. Some Simple Tests 1. Put some chloroform in tomato catsup or other table sauces and shake it vigorously, pour it off into a saucer and let it stand until it evaporates. If crystals are left, they are probably benzoic acid. 2. Put a teaspoonful of milk in a teacup, with twice the amount of HC1 to which has been added a drop of ferric chlo- ride. Mix them by rotating the cup gently. Put the cup in a vessel of boiling water and let it stand for 5 minutes. If formaldehyde is present, it will be shown by purple or lavender color. 3. Mash some canned peas or string beans with a spoon. Put a teaspoonful of it in a teacup with 3 teaspoonfuls of water and 30 drops of HC1. Set the cup in a pan of boiling water. Drop a bright iron nail into the cup and keep the water boiling for a few minutes, stirring the mixture frequently ; if copper is present, it will plate the nail copper color. 4. (a) Stew \ teaspoonful of ground coffee in one half cup of boiling water and cool. Dilute with water, if it is dark colored, and add iodine solution drop by drop. Color ? Conclusion ? (6) Same for ground cloves, mustard, cayenne, etc. (c) Add a teaspoonful of finely ground coffee to one half glass of cold water. Pure coffee will float, and its adulterants, chickory, roasted cereals, etc., will sink. Pure coffee will not appreciably color the water, while chicory will leave a brownish trail as it sinks. Limit test to 5 minutes. 5. Place a tablespoonful of tea in a wide-mouthed bottle and shake it with six times its volume of cold water. Strain the water through a sieve and any insoluble mineral substances used on the leaves will settle. 6 Put some butter or oleomargarine in a spoon and heat over a lamp. If it is fresh butter it will boil quietly with much FOODS AND DIETARIES 253 foam. Oleomargarine or poor butter will sputter and crackle like a green stick burning, and with little foam. 7. Add 2 or 3 tablespoonfuls of Halphen's solution l to an equal amount of salad oil and heat the mixture in a vessel of boiling salt solution, for 10 or 15 minutes. A reddish color indicates cottonseed oil. 8. (a) Hold an egg between the eye and the light by put- ting it at end of a tube and looking toward a bright light. Presence of dark spots shows that the egg is not perfectly fresh ; absence of air cell at one end shows the same. In eggs long packed, the yolk or the white slightly adheres also, or the egg will adhere to the shell on one side and also have a musty odor. (6) Another test. — Make a weak salt solution of about 10%. If the eggs float in it, they are not fresh. 9. Rinse out a glass with small amount of vinegar and allow to stand a number of hours or over night. If the vine- gar was made of wine, there will be a wine odor left in glass ; if of apples, then a fruity odor. 10. Place a teaspoonful of lemon or orange extract in a test tube and add 2 or 3 drops of hydrochloric acid. No change indicates natural color, turmeric, or naphthol orange (harmless); pink indicates tropseolin or methyl orange; partial decolora- tion, Martius yellow ; complete decoloration, dinitro cresols. e. Table Waters Note. — $12,000,000 of bottled water sold to public and more than $ 1,000,000 imported each year. Most carbonated waters receive their sparkle through artificial treatment by adding the gas of soda water or " vichy." Questions 1. What are the pure food laws of your state ? 2. Do the pure food laws of your state protect you from adulterated foods shipped in from other states ? 1 Halphen's solution is made by dissolving J teaspoonful of flowers of sul- phur in some bisulphide of carbon ; mix this with an equal volume of amyl alcohol. 254 FOODS AND DIETARIES 3. Should there be a uniform pure food law for all states ? Give your reasons. 4. When are foods said to be adulterated ? 5. How can you tell good butter from poor ? From oleo- margarine ? 6. How may foods be adulterated ? Name some adulterants. 7. How can you detect the presence of formalin in milk ? 8. How find out whether copper is used to give a green to pickles, etc. ? 9. How find out whether sausages are adulterated ? Coffee ? Pepper? Tea? 10. How distinguish olive oil from cottonseed oil ? .•..':•<• - . f^, Special Reports 1. The pure food laws. 2. Deleterious ingredients in foods. 3. Pure milk and the public health. 4. Try to justify the following statement: "Ten billions of dollars are expended annually in the United States for food, clothing, and shelter. With greater knowledge and efficiency, better satisfaction could be obtained and one billion dollars be saved for higher things." References Hunter, Essentials of Biology. Chap. XXIV. Bigelow and Howard, " Some Forms of Food Adulteration and Simple Means for Their Detection." Bulletin 100, U. S. Department of Agricul- ture, 1906. Howard, "The Use of the Microscope in Food Adulteration." Sepa- rate 455, Yearbook, U. S. Department of Agriculture, 1907. Melvin, "the Federal Meat Inspection Service." Circular 125, U. S. Department of Agriculture, 1908. Weyl, W., " Pure Milk and Human Life." Success Magazine, March, 1909. Smith, " Deleterious Ingredients in Foods." Science, February, 1910. Macewen, Hugh, Food Inspection. Patrick, " Household Tests for the Detection of Oleomargarine and Renovated Butter." Farmers' Bulletin No. 131, U. S. Department of Agriculture, 1901. Wiley, Foods and their Adulteration. FOODS AND DIETARIES 255 PROBLEM XLIV A study of some medical frauds?- I. NOSTRUMS a. The Bracers i Note. — " Gullible America will this year spend some $75,000,000 on patent medicines and incidentally with them swallow huge quantities of alcohol, much opiates and nar- cotics, and be most scandalously humbugged." FIG. 59. — Showing percentage of alcohol in certain liquors and patent medi- cines. A test tube represents a glass, a, beer, 5% ; 6, claret, 8% ; c, cham- pagne, 9%; d, whisky, 50% ; e, well-known sarsaparilla, 18% ; /, much-adver- tised vegetable compound, 20% ; g, celery compound, 21% ; h, popular blood bitters, 25% ; i, another sarsaparilla, 26% ; j, tonic, 28% ; k, another brand of bitters, 37% ; I, another bitters, 44%. Observations. — 1. Note the percentage of alcohol in the fol- lowing patent medicines by comparing the test tubes. Note. — The tubes should be filled with water or alcohol to the indi- cated heights and the contents colored with carmine to make 1 Adapted from Adams, The Great American Fraud, American Medical Association, Chicago. 256 FOODS AND DIETARIES them more of an object lesson. Let each one represent a glass of the compound considered. 2. How much alcohol in tonic j (Fig. 59), as compared with a bottle of beer of the same size ? 3. How many bottles of champagne or claret will equal the alcohol value of one bottle of tonic j (Fig. 59) ? 4. How much beer would a toper need in order to equal in alcohol value one bottle of bitters I (Fig. 59) ? 5. Get the names of as many patent medicines as you can at drug stores, such as " spring tonics," " invigorators," " swamp roots," " nerve builders," " bitters," etc. Conclusion. — Can you decide why most of the above might have a decided " tonic " effect for a short time ? Note. — Most patent medicines cure by faith and the stimu- lus of the contained alcohol or opiates. Explain how the effect of these medicines might cause most people to write glowing testimonials. b. Ozone Preparations (Optional) Note. — These and similar preparations are being put on the market in answer to a demand for something to kill disease germs. The public mind blames germs for all diseases. Observations. — 1. Get the names of as many patent medicines as claim to cure all such germ diseases as asthma, bronchitis, hay fever, tubercu- losis, fevers, etc. 2. Look up ozone and its properties. (See any good text in chem- istry, or a dictionary.) 3. What do these medicines profess to cure ? Note. — Notice that the list includes (1) all diseases that begin with fever ; (2) all catarrh ; (3) all contagious diseases ; (4) all inflammation ; (5) all the results of im- pure and poisoned blood. 4. What is the taste of the so-called ozone compounds ? Note. — The taste indicates the presence of an acid. 5. Warm some of one of these compounds with HC1. Is there an odor something like that from burning sulphur matches ? Are there bubbles given off ? Wet a piece of filter paper with a potassium bichromate solu- tion and expose to the escaping fumes. Does it turn the paper green ? Note. — A green color shows the presence of sulphurous acid. FOODS AND DIETARIES 257 Study the analysis of one of them, which follows : — Sulphuric acid . . . . . &ofl%. Sulphurous acid ^ of 1 %. Water about 99%. Note. _ Sulphuric acid is oil of vitriol. Sulphurous acid is much like it. Both are poisons. Conclusions. — 1. What have you learned about the composition of tliis compound ? 2. Do you think that it is necessary to buy such patent medicines ? jVoje. — Their acids are known to be positively injurious to health. 3. Find out the cost of the ingredients given in the analysis. Also the cost of a bottle of the medicine as sold at the drug store. How much profit is there on the original cost ? Who gets most of it ? 4. Guinea pigs were treated with one of these compounds, and' they died, in varying periods of time. (See report of Lederle Laboratories, 518 5th Avenue, New York, of October 21, 1905.) What does that indi- cate as to its probable effect on other similar, animals and even man ? 5. Why have such states and communities as North Dakota, San Fran- cisco, and Lexington, Ky., forbidden their sale ? c. The Subtle Poisons 1. HEADACHE AND NEURALGIA CUBES Note. — Most headache powders depend for their action on the presence of acetanalide. Acetanalide depresses heart action, and many deaths are directly charged to its use in various antipain preparations. Observations. — 1. Place a small quantity of a headache pow- der in a dry test tube with a like amount of zinc chloride. Heat it slowly until fumes arise. Hold a wood splint in its fumes. Is the splint colored by the fumes ? Note. — The presence of a red or yellow color, or both, indicate? the presence of acetanalide, a substance unsafe to take without the advice of a physician. 2. Test as many other alleged headache powders as possible for acetanalide. Note. — If any of the powders do not respond to the test for acetanalide, they should be tested for other dangerous drugs. SHARPE'S LAB. MAN. — 17 258 FOODS AND DIETARIES 3. Test some of the advertised quinine tablets in the same way. 4. Get a list of all the " headache cures," antipain, and neu- ralgia cures you can. 5. List the different troubles, that a headache powder claims to cure. 6. Are there any sample medicines being distributed in your neighborhood ? Conclusions. — 1. Write a paragraph or so, telling what you have learned regarding most so-called headache cures. 2. Why is one of these compounds called " a good repeater " ? 3. What is the general reason for distributing such sample medicines ? 2. CATARRH AND OTHER CURES Observations. — 1. Many antipain catarrh remedies and sooth- ing sirups contain opium or cocaine. Inquire the uses of such remedies as codein, laudanum, paregoric, soothing sirup, etc. Note. — Such remedies contain morphine, opium, or cocaine. 2. Get a list of as many so-called catarrh cures as possible and note their claims. Note. — Dozens of these catarrh cures have been tested, and are known to contain much cocaine. 3. Are there any " sample " medicines being distributed on the streets or otherwise in your neighborhood ? If so, what are they ? 4. Scan the daily papers for advertising matter concerning such remedies as the above. List the names of the remedies and the companies selling them. Which papers carry the most of such advertising ? Conclusions. — 1. Explain the statement credited to a New York woman concerning her two young children : "Just one teaspoonful of soothing sirup, an7 they lay like dead till morning. " 2. Why should shop girls and others be likely to call for Blank's Catarrh Cure ? 3. Only when is it wise to take " patent " medicines of any sort? FOODS AND DIETARIES 259 4. What general reputation do the papers carrying the above advertisements bear ? 3. PREYING ON THE INCURABLE Note. — Such diseases as consumption, cancer, dropsy, heart disease, deaf ness,* epilepsy, fits, and paralysis are probably in- curable by medicines. Advertisers professing to cure these diseases with medicines are therefore virtually "birds of prey" and are preying on humanity. Observations. — 1. Scan the daily papers for advertisements that profess to cure any of the above diseases. 2. Do such fakirs "guarantee" their remedies? List some that do. 3. What is malt whisky listed to cure ? 4. Do any claim to " return your money if not satisfied " ? 5. Can you find any offering to send medicines free ? 6. Do any advertise " no cure, no pay " ? Conclusions. — 1. Why is it that people allow themselves to be humbugged into buying such remedies as listed above ? 2. Why should state and government aid be asked in order to suppress such fraud ? 3. What can you do to help ? 4. What precautions should you think advisable if you were about to buy a house, an automobile, or even a pair of shoes ? Would ordinary testimonials suffice ? 5. Do people observe the same precautions when they set out to buy health ? II. QUACKS AND QUACKERY a. Sure Cure School Observations. — 1. Look for advertisements that profess to " cure where all others fail." Such are surely " quacks," and those who patronize them are scarcely better. 260 FOODS AND DIETARIES 2. List as many firms as you can find who profess to be " sure cure." 3. Can you see any reason for the remark made by a mem- ber of a quack firm, " Keep 'em sick by suggestion " ? Conclusions. — 1. Should you be likely to patronize any physician who says he can " positively cure " ? 2. What reasons can you give for never patronizing any firm through the mails ? 3. Give your reasons for never patronizing any "secret remedies," also "no cure, no pay" firms. 4. What class of newspapers do you find advertising "spe- cifics," " sure cures," etc.? 5. Why should such papers be classed also as quacks and certainly lacking in moral sense ? b. Miracle Workers Observations. — 1. Look up and list all firms claiming to cure by (1) "Magnetic healing," (2) "'Healers," (3) « Radiotherapy," (4) "Vibrations," (5) "Magnetic Belts," (6) "Magnetic Shields," (7) " Health Homes," (8) "Supernatural Power," etc. 2. Tabulate the above, showing just what firms so advertise and what they claim to cure, thus : — l 2 3 4 5 6 7 8 9 OTHERS Firms . . . Diseases they claim to cure . . FOODS AND DIETARIES 261 Conclusions. — 1. Who are most susceptible to such adver- tisements ? 2. Show that there is truth in Barnum's statement that "The American people like to be humbugged." 3. Why do "miracle workers" usually not remain in one place long at a time ? c. The Specialist Humbugs Note. — "Specialist humbugs" diagnose by mail and send doses by express. They " consult " by a series of ingenious letter forms. Observations. — 1. Look for such advertisements as "Don't undergo an operation, come to me and spare yourself the tor- ture of the knife," etc. 2. Do any claim to " continue the treatment after a few- months free of charge " ? 3. Do any claim to cure by " absorption methods " ? 4. Do any claim to be " editorially indorsed," or backed by any " religious paper," or claim a " special interest " in your case at " reduced rates " ? Note. — If you come across any such statements as just quoted, you may be sure they are quacks. 5. Do they address you as "Dear Friend" or "Dear Mr. So- and-so " or " My Dear Correspondent " in answer to any let- ters ? If so, and you are determined to give them a trial, an- swer that, since a promise is made to cure you, you will deposit in a reputable bank the full price of the treatment, to be paid as soon as the promises are fulfilled, and not before. WTiat reply do you receive ? Conclusions. — Write a paragraph on the methods of humbug specialists and how to distinguish them. d. The Scavengers Note. — By scavengers, we may perhaps rightfully designate all who claim to cure various diseases, including the drink and the drug habit, by mail. 262 FOODS AND DIETARIES Observations . — 1. Look for any advertising matter coming under the above headings. Just what do they profess to do? 2. Do they attempt to get the indorsement of prominent peo- ple? 3. Do any pretend to be physicians ? 4. Write the nearest drink cure company. What do they profess to do ? Note. — Any such companies not professing to certainly cure, especially " where all others fail," or take pay for cases they know to be incurable, may be classed as reputable and quite likely doing good work. 5. Do any firms profess to send treatment by mail C.O.D.? 6. Do any profess to be " strictly confidential " ? 7. Do any states forbid advertising of this sort ? Note. — Some communities have passed such laws, but they have been largely a farce, as some temperance laws have been. In other words, many people do not realize how scandalously they are being humbugged, and patronize the "scavenger" type of firms by stealth. If all communities or states would cooperate, and the moral sense of the people were aroused through education, a much different story might be told. Conclusions. — 1. Show why government aid should be in- voked in dealing with such advertisers as considered under this section. 2. Write a paragraph telling how you would recognize fakirs designated as " scavengers." Questions 1. Why are some patent medicines well called " bracers." 2. Why are some patent medicines best known as "repeat- ers"? 3. Whfffe effect has acetanalide on the heart ? In what medi- cines is it likely to be found ? How detect it ? 4. Are " strictly confidential " firms of good repute ? Explain. 5. What conclusion is evident whenever you see advertise- ments with photographs of " cured " people inserted ? FOODS AND DIETARIES 263 6. How distinguish " specialist " humbugs from " scaven- gers"? 7. Name some " habit-forming " agents. Why is their in- discriminate sale and use a menace to the public welfare ? 8. Show how the following is true : " Most illness results from carelessness, ignorance, or intemperance of some kind." Special Reports 1. The great American fraud. 2. The specialist humbugs. 3. The scavengers. 4. The "sure cure" school, 5. Harmfulness of headache mixtures. 6. Some "habit-forming" agents. References Hunter, Essentials of Biology. Chap. XXIV. Adams, The Great American Fraud. " A Grewsome Record of Convictions." Public Health Defense League, New York, 1910. Willis, " What Whiskey Is." McClure's Magazine, April, 1910. Russell, Isaac, " The Danger in the Drug Store." Pearson's Maga- zine, June, 1910. The Propaganda for Reform in Proprietary Medicines. American Medical Association, 103 Dearborn Avenue, Chicago. Kebler, L. F., " Habit-forming Agents. " Farmers' Bulletin No. 393, U. S. Department of Agriculture, 1910. Kebler, L. F., and others, "Harmfulness of Headache Mixtures." Farmers' Bulletin No. 377, U. S. Department of Agriculture, 1909. Forbes, E. A., "What not to do for a Headache." World's Work, June, 1910. Johnson, E. B., "The Drug Clerk a Poor Doctor." World's Work, July, 1910. SUMMARY II A summary of stimulants and narcotics, with some reference to patent medicines. Note. — None are necessary to enable one to make the great- est success in life. 264 FOODS AND DIETARIES I. NARCOTICS (Eelieve pain, and tend to produce sleep.) 1. TOBACCO. a. Has nicotine, — a poison. Harms by irritating and may tend to produce ulcer of the mouth, hoarseness, and throat troubles. May impair digestion. Affects the heart beat. Cigarettes impair physical health and mental vigor. Out of 100 boys in New York city charged with crime 99 are cigarette smokers. 2. OPIUM. a. From juice of poppy. Sleep-producing. 1. Paregoric equals opium, alcohol, camphor, and other drugs. 2. Laudanum equals opium, alcohol, and water. 3. MORPHINE. a. From opium, and four times as strong as opium. Neither should be taken except by advice of a physician. 4. MANY PATENT MEDICINES. a. Many contain much alcohol. The sick think they help because of the stimulating effect of the alcohol at the time. b. Soothing sirups contain opiates. c. Many remedies for colds and catarrh contain opium, morphine, and cocaine. II. STIMULANTS (Cause organs to act more vigorously.) 1. TEA. a. Black tea the best. Made by pouring boiling water on the leaves and pouring off the infusion. May produce dyspepsia and nervous disorders. 2. COFFEE. a. Stimulates the brain and heart, and may disturb diges- tion and produce nervousness and sleeplessness. 3. ALCOHOL. a. Thirst for this affects over 1,000,000 of our people. May produce a bad habit and wreck both body and character. FOODS AND DIETARIES 265 III. ALCOHOL ( Special ) (General effect to produce poverty and crime.) 1. AMOUNT IN LIQUORS. a. 3-12%. Beer, stout, porter, ale, champagne, cider, etc. b. 15 to 20%. Sherry, gin, port wine, and many patent medicines. ($75,000,000 worth of patent medicines contain al- cohol.) c. 55%. Whisky. 2. AMOUNT CONSUMED. a. Beer, 1,000,000,000 gallons. (Requiring 60,000,000 bush- els of grain, — a great loss.) b. Wine, 2,000,000 gallons. c. Whisky, 4,000,000 gallons. 3. ALCOHOL IN HEALTH. a. Has no good effect. b. Weakens instead of strengthens. c. Weakens digestion, and decreases value of food con- sumed. 4. ALCOHOL AND DISEASE. a. Affects liver, kidneys, heart, blood vessels, and nervous system. b. Said to cause Bright's disease, gout, heart disease, and ca- tarrh, and weakens the white corpuscles, or those cells that naturally fight off pneumonia, tuberculosis, etc. 5. NATIONAL Loss THROUGH LIQUOR. (One thousand arrests per day through drunkenness, and one half the number of destitute children made so by alcohol.) a. Ruins homes, bodies, and character. b. Ten thousand of our convicts victims from its use, and 30% of the inmates of almshouses. c. Courts disease, suffering, and death. d. Money loss per year at least $1,200,000,000. Gladstone said : " Alcohol is productive of greater evils 266 FOODS AND DIETARIES than the combined scourges of war, famine, and pesti- lence." 6. ALCOHOL AS A MEDICINE. a. It has never been known to cure any disease, but may help to do so. 7. CALLED A POISON (as it causes sickness and death when introduced into the body). a. Destroys will power. b. May affect the internal organs. 8. DANGERS FROM ITS USE. a. Weakens body and mind, thus making men more liable to disease and crime. b. At least one in 10 occasional drinkers become intem- perate. c. Affects tissues of the young more than those of the adult, or past 30 years. (No greater patriotism can be displayed than to fight this evil, and nothing requires greater courage.) ADAPTATIONS FOR DIGESTION, CIRCULA- TION, AND ABSORPTION OF FOOD PROBLEM XLV To study the digestive system of a frog, in order better to understand that of man. Materials. — Frogs preserved in 4% formalin. Some with ventral body wall removed, others for optional dissection by the pupil. Split specimens of frogs' stomachs. Portable micro- scope. Chart showing digestive system of frog. a. General Study and Adaptations Observations. — 1. Note the looseness of the skin. Are the muscles forming most of the ventral body wall thick or thin? 2. Find a large, reddish brown, lobed organ (liver) which nearly covers the other organs. How many lobes has the liver ? 3. Lift the liver to one side, and find a small greenish body (bile sac or gall bladder) on one side of the liver and between its lobes. To what does it seem to be attached ? 4. Open the mouth of the frog and force a small probe down its throat into its continuation (the gullet or esophagus). This leads to an enlargement (stomach) which in turn leads to a long slender tube (small intestine). 5. Look for a thin membrane (mesentery) holding the coils of the small intestine in place. Is it along the full length of the small intestine ? 6. Note that the small intestine leads into a larger tube 267 268 DIGESTION, CIRCULATION, AND ABSORPTION (large intestine) which empties into the cloaca. How does the large intestine compare in length with the small intestine ? 7. Look between the stomach and first bend of the small intestine and find a yellowish body (pancreas). Where does it seem to be attached ? 8. Examine the split stomach and find folds and ridges of the inner wall. In what direction do they run, lengthwise or circularly ? 9. Examine a mounted section of the small intestine of a cat or a dog through the compound microscope, and note the small elevations of its inner wall or lining, called villi. De- scribe the appearance of a villus. Conclusions. — 1. Name the digestive organs in order, begin- ning in the mouth, and including all glands. 2. What advantage do you think there is in having the small intestine coiled ? Why not the large intestine coiled ? (See Absorption, in any advanced Physiology, or the instructor may mention it here.) 3. Do the ridges of the stomach affect its absorbing area in any way? Can you suggest any use of the villi of the small intestine ? 4. Can you suggest any use for the mesentery, other than support of the intestine ? 5. What are the more important adaptations of the alimen- tary canal for the digestion of food ? For the absorption of food? b. Drawing (Optional) Sketch the food tube, extended so it will show. c. Comparison with Man Materials. — Charts and manikins of man, showing the di- gestive organs, or Figure 60. Set of teeth. Piece of tripe. Observations. — 1. Compare the digestive organs of the frog with those of man. What organs are similar ? What organs present in man are not found in the frog ? DIGESTION, CIRCULATION, AND ABSORPTION 269 2. Study a piece of tripe. What is tripe ? What advan- tage in the " honeycomb " arrangement ? 3. Why does a man need teeth ? Are they all of the same shape ? 4. (Home work.} With the aid of a small mirror count the teeth of each jaw. Answer the following questions: — a. The total number on each jaw ? b. The number of broad teeth (incisors) in the front of each jaw? c. The .number with one point on the biting edge (canines) ? d. The number with two points on the biting edge (premolars or bicuspids) ? e. The number with more than two biting points (molars) ? f. Compare your results with Figure 61. How do they agree ? Differ ? g. Examine the teeth of a cat or a dog. What difference do you find FIG. 60. — Front view of the or- as to the kind and number of teeth ? What kind of food do they eat ? Conclusions. — 1. Is there any connection between the food and the kind of teeth found in any animal ? 2. What is the use of the teeth ? 3. Why is thorough chewing a gans of digestion of man. a, c, e, colon ; d, duct of the gall bladder ; dm, diaphragm ; g, gall bladder ; h, hepatic duct from the liver ; k, kidney ; I, i, small intestine ; Iv, liver : n, opening of the bile duct into the small intestine ; oe, esoph- agus ; pn, pancreas ; r, rectum ; st, stomach ; ftp, spleen ; vx, vermiform appendix. necessary first step in digestion ? 4. Through what organs does the food pass in the course of its passage through the body of man ? 270 DIGESTION, CIRCULATION, AND ABSORPTION Questions 1. What is meant by Fletcherism ? 2. ' Why is it advisable that the teeth be examined by a dentist at least twice a year ? 3. What are some of the causes of indigestion ? 4. Why is regularity in eating of importance ? <5. What causes teeth to decay ? 6. Why should the teeth be brushed often ? xj. Which of the human teeth are fitted for cutting ? For tearing ? For grinding? 8. Examine your own FIG. 61. -Mounted set of adult teeth. Right teeth and report just what side, i, incisors ; c, canine ; p, premolars, ' m, molars. (Photograph by Davison.) teeth are present, what are missing, and whether any are coming in out of place. Write a report as home work and bring it to the laboratory. 9. What glands furnish digestive juices ? 10. What are the two parts of the trunk cavity in man? How are they separated ? SUMMARY III A summary of the digestive system of man. A. PARTS. 1. Alimentary canal. a. Mouth. (1) Tongue. Teeth, Kinds, structure and care of. b. Pharynx. c. Esophagus. DIGESTION, CIRCULATION, AND ABSORPTION 271 d. Stomach. e. Intestines. Small and large. 2. Assisting glands. a. Uses. (1) To secrete juices for softening and dissolving food so that it may be absorbed into the blood by osmosis. 6. Kinds. (1) Salivary furnish (2) Gastric furnish (3) Pancreatic furnish (4) Liver furnishes (5) Intestinal furnish B. EXTRA. 1 . Special functions of the liver. a. A gland to secrete ?>. A storehouse of c. A guardian to destroy _ that otherwise might enter the blood. PROBLEM XLVI How foods are chemically prepared for absorption into the blood. a. In the Mouth 1. ACTION OF SALIVA Materials. — Cornstarch paste, grape sugar (glucose), saliva, test tubes, Fehling's solution, alcohol lamp or Bunsen burner, paraffin wax. Method a. — Put some corn starch in a test tube of cold water and shake it. Heat it until it boils. Set it aside to cool. Observations. — 1. Does the starch seem to dissolve in the cold water ? Its color ? 2. Has the starch that was boiled disappeared from view, or dissolved, or is it still seen ? Conclusion. — Is starch soluble in cold water? In hot water ? Method b. — Put some grape sugar in a test tube with water and boil it. Add Fehling's solution and boil it. 272 DIGESTION, CIRCULATION, AND ABSORPTION Observations. — 1. Does the grape sugar dissolve in water ? 2. What color is produced by boiling when Fehling's solu- tion is added ? Conclusions. — 1. How determine whether grape sugar dis- solves in water ? 2. Review the test for the presence of grape sugar. Method c. — Add some fresh saliva1 to a small amount (| test tube full) of diluted starch paste. Set it aside in a warm place, for ten minutes or more. Then test for grape sugar.2 Test some of the saliva for grape sugar and likewise test the starch paste. Observations. — 1. What effect when Fehling's solution and saliva are boiled ? 2. What effect when starch paste and Eehling's solution are boiled ? 3. What effect when the mixture of starch paste and saliva are boiled with Fehling's solution ? Conclusions. — 1. Is there any grape sugar present in the saliva ? Is there any grape sugar present in the starch paste ? 2. Is there any grape sugar in the mixture of starch paste and saliva after standing for a short time ? 3. How can you account for the sugar in the starch paste after treating it with saliva ? 4. What is the effect upon the solubility of starch after treating it with saliva ? 5. What is digestion ? 6. Chew a piece of cracker slowly. Can you account for the sweetish taste ? (Homework.) b. In the Stomach 1. ACTION OF GASTRIC JUICE (OPTIONAL) Materials.— Minced white of boiled egg, hydrochloric acid, pepsin, 5 numbered test tubes, beaker, and cracked ice in a container. 1 Fresh saliva may be procured by first rinsing the mouth, then chewing Paraffin wax and collecting the saliva in a test tube. 2 The sugar present is really maltose. The tests for the two sugars are the DIGESTION, CIRCULATION, AND ABSORPTION 273 Method. — In No. 1 place minced white of egg + water. In No. 2 minced white of egg +.2% HCL. In No. 3 minced white of egg -f .2% HC1 + pepsin. Numbers 4 and 5 as No. 3. Place Nos. 1, 2, and 3 near the register or radiator, or in a water bath, so as to keep them at about blood heat for a few hours. Place No. 4 in a vessel surrounded with cracked ice, or in as cool a place as possible for a few hours. Place No. 5 in boiling water for 15 or 20 minutes, then set it aside with Nos. 1, 2, and 3. Observation. — Test No. 1 with the biuret l test for presence of peptone. Result? Conclusion. — What is your conclusion as to the action of water on proteid ? Observation. — Test No. 2 as No. 1 was tested. What do you observe ? Conclusion. — Does hydrochloric acid change proteid into a soluble state ? Observation. — Test No. 3 as you tested Nos. 1 and 2. What do you observe ? Conclusions. — 1. What is your conclusion as to the effect of HC1 + pepsin on proteid ? 2. Is the resulting substance soluble or insoluble ? Note. — If the proteid has been made soluble by the action of pepsin, it is because it has been made into a soluble substance known as peptone. Observation. — Test Nos. 4 and 5 as Nos. 1, 2, and 3 were tested. What do you observe ? Conclusions. — 1. What are your conclusions as to the effects of high temperature and of low temperature on the action of pepsin on a proteid ? Explain. 2. Write a connected account of all your conclusions here. Try tabulating your results. c. In the Small Intestine 1. ACTION OF PANCREATIC JUICE (OPTIONAL) Materials. — Pancreatin, sodium carbonate or baking soda, starch, pro- teid, olive oil or butter, water bath. Note. — Artificial pancreatic juice may be made by mixing 10 grains of pancreatin with 20 grains of baking soda and adding 200 cc. of water. Method a. — Add some dilute starch paste to a test tube half full of 1 Biuret Test. — Add caustic soda in concentrated solution. To this add a few drops of solution of "copper sulphate. A rose-pink color shows the pres- ence of peptones. Violet color indicates the presence of unchanged proteid. SHARPE'S LAB. MAN. — 18 274 DIGESTION, CIRCULATION, AND ABSORPTION artificial pancreatic juice. Keep it in a warm bath at about blood heat for a few hours. Then test with Fehling's solution. Observation. — What is the result when the mixture is tested with Fehling's solution ? Conclusion. — What is the action of pancreatic juice on starch ? Method b. — Shake a little melted butter or olive oil in a test tube half full of artificial pancreatic juice. Note. — Shake some oil and water in a test tube. Add a few drops of ammonia, and shake vigorously again. The resulting milky colored mixture is called an emulsion. Where have you heard of it before ? Observations. — 1. What is the appearance of the mixture ? Note. — The oil is now in small microscopic drops scattered throughout the water. 2. What is the result of shaking the-oil or butter with pancreatic juice ? Conclusion. — What is one result of the action of pancreatic juice on oils and fats ? Method c. — Add some blue litmus solution to \ test tube of milk. Add some pancreatic juice and let the mixture stand in a warm bath at blood heat for a few hours. " ' *" Observation. — What is the final color of the mixture ? Conclusion. — What has evidently been formed ? Note. — The fats and oils are finally split into glycerin and fatty acids and absorbed in this form. Method d. — Add some proteid (minced white of egg) to a test tube half full of artificial pancreatic juice. Keep at blood heat for a few hours. Shake occasionally. Test for peptones as under study of gastric juice. Observation. — What is the appearance of the contents of the tube ? Conclusions. — 1. Is the egg digested ? Has any other digestive juice acted in the same way ? 2. Write a summary of your conclusions regarding the effect of pan- creatic juice on nutrients. 2. ACTION OF BILE (OPTIONAL) Materials. — Ox gall or bile, olive oil, white of egg, pancreatic juice, test tubes. Observations. — 1. Add some bile to minced white of egg in a test tube. Also to some starch. Results when kept in warm bath for a few hours ? 2. Add pancreatic juice to minced white of egg in two tubes. Add bile to one of the tubes. In which does digestion take place more quickly ? 3. Put proteid in two test tubes. Add bile to one. Let stand in warm place until putrefaction occurs. DIGESTION, CIRCULATION, AND ABSORPTION 275 Conclusions. — 1. Does bile digest proteid ? Starch ? 2. Does bile aid pancreatic juice ? 3. Does bile prevent putrefaction ? Questions 1. What is a food ? What is a perfect food ? 2. Explain fully the digestion of a piece of bread and butter. 3. Soup is absorbed quickly. Why is it good to eat at the beginning of a meal ? 4. Why is the chewing of tobacco and gum generally harmful ? 5. In which of the digestive organs is but one kind of digestive juice furnished ? 6. In what digestive organ are three juices poured ? 7. What nutrient digested in only one organ ? 8. What nutrients digested in two organs ? 9. Why should starchy foods remain longer in the mouth than meat or proteid ? 10. Why is half-cooked or soggy bread harder to digest than raw wheat ? Which one needs the most saliva ? Why ? 11. For what purpose does the body use lean meat ? 12. Name three foods easily digested. Three foods hard to digest. 13. The uses of starch or sugars in the body ? Of fats ? 14. Explain the biology of the following : — " Now good digestion wait on appetite, And health on both." — SHAKESPEARE. Special Reports 1. Common causes of illness. 2. Effect of lack of exercise on digestion. 3. Health fads and foods. 4. The harm done by ignorant cooks. 5. Effect of alcohol on digestion. 6. Causes and prevention of dyspepsia. 276 DIGESTION, CIRCULATION, AND ABSORPTION References Hunter, Essentials of Biology. Chap. XXV. Eddy, Textbook in General Physiology and Anatomy. Davison, The Human Body and Health. Chap. VI. " Influence of Food Preservatives and Artificial Colors on Food." Chemical Bulletin 84, Parts 2, 3, U. S. Department of Agriculture. " The Waste of Overeating." Success Magazine, March, 1910. Cantley, E., "Starch Digestion in Babies." The Lancet, 111, February, 1910. Day, Edna E., "Digestibility of Starch as affected by Cooking." Bulletin 202, Experiment Station, Washington, D.C. Fisher, Physiology of Alimentation. SUMMARY IV A summary of digestion. 1. Definition. The process of food, so that it may pass through the walls of the into the , and thence from the into the tissues to the cells. 2. Accomplished by, a. Mechanical means. (1) Chewing muscles. 2. Teeth. 6. Chemical means. (1) Action of acids and alkalies on foods (bile, hydrochloric acid, etc.). c. Organic means. (1) Action of ferments. (a) Ptyalin in the mouth. (6) Pepsin in the stomach, (c) Pancreatic juice in the small intestine, etc. 3. Details of chemical and organic means. a. In mouth. (1) Saliva acts on to change it to Food should be chewed on an average about times, to well mix it with Good looks and taste of food start the flow of Chewing gum and tobacco wastes ?>. In stomach. (1) Pepsin changes __,.,., to which are DIGESTION, CIRCULATION, AND ABSORPTION 277 curdles milk. Soup for the first course of a dinner starts the flow of and temporarily satis- fies the craving for food. This tends to prevent c. In the small intestine. (Nearly all digestion carried on here.) ( 1 ) Pancreatic juice acts on (2) Bile aids in absorption of (3) Intestinal juice acts on d. Large intestine. (1) Practically no digestion. e. Fill in the following summary : — GLANDS LOCATION JUICE ENZYMES OR FERMENTS ACTION OF REASON FOR ITS ACTION 1. 2. 3. 4. 5. 6. PROBLEM XLVII A study of where and how digested foods pass into the blood (absorption). Materials. — Tripe, and charts showing the plan of absorption and the villi of the human intestine. Note. — Observe how the mucous membrane of the small in- testine is thrown into ridges and small elevations (villi). a. The Villi Observations. — Note the microscopic blood vessels (capil- laries) entering a villus. If the liquid food is on the outside of the villus, how might it get inside the blood vessels ? Note.— The small blood vessels beginning here finally unite, and carry proteid, water, salts, and sugar to the liver. 278 DIGESTION, CIRCULATION, AND ABSORPTION Here may be also found the beginnings of other small tubes that carry emulsified fats and oils to a vein under the left collar bone. These small tubes are called lymph capillaries. As they carry emulsified fats and oils (for a time after meals) they are milky colored and are thus called lacteals (lac = milk). Conclusion. — Show how the villi may be said to " lick up the di- gested food." b. How Foods are Absorbed 1 Foods into the are absorbed FIG. 62.— Diagram of the structure of a block mtO trie blood vessels of tissue smaller than a pin's head, cut from and lacteals of the villi the wall of the small intestine, a, mouths Qf the intestinal tract,1 of intestinal glands ; 6, villus cut lengthwise to show the blood capillaries and white lacteal and get into within ; e, lacteal vessel sending branches to latioil in the following many villi ; i, intestinal glands ; m, artery ; wavs . v, vein ; I and t, mus'cular coats. . ^ 1. Osmosis. ii-x- Where have you change through a moist membrane, heard of this before ? 2,. Filtration. Forced through by pressure when the mus- cular walls of the intestine contract. 3. Imbibition. About as a sponge absorbs water, or as a towel does the same. i Nine tenths of the food that reaches the blood is absorbed by the villi of the small intestine. There are fully 20,000 villi to the square inch. DIGESTION, CIRCULATION, AND ABSORPTION 279 c. Paths of Absorbed Foods Observations. — 1. The absorbed foods now take two different directions ; all but the fats go at once to the liver, through the portal vein; while the fats are carried by the main lymph duct (thoracic duct) to a vein under the left collar bone as indicated above, therefore the fats do not pass directly through the liver but to the heart first. What are the lacteals ? Note. — Study Figure 63 carefully, forming your own questions and answers. 2. Fats are absorbed chiefly as fatty acids and glycerin. The cells of the villi reconstruct the fatty acids and glycerin into the microscopic fat parti- cles which are passed on into the small tubes that finally converge to form, in part, the thoracic duct which conveys this fatty food into the general circula- tion. 3. The digestive tube is, then, a mus- cular tube of varying diameter, lined by FIG. 63. — Diagram show- mucous membrane. The muscular coat ing how the food reaches 1 , i /> -, i . . •, . . , the heart to he sent with propels the foods and mixes them with the blood to all parts of the liquids present; some of these the body, liquids merely soak the food, others act on it chemically, while mucus serves to lubricate the surface. It seems that the glands lining the inner surface of the digestive canal are not sufficient, so several extra glands are provided, such as the salivary glands, pancreas, and liver. Find these glands on a chart. Conclusion. — Write a brief summary of the paths absorbed foods take in reaching the heart. Copy Figure 63. 280 DIGESTION, CIRCULATION, AND ABSORPTION d. Summary of Adaptions for Absorption Fill in the following table : — FOODS WHERE ABSORBED FORM ' ADAPTATIONS FOR PATH TO HEART 1. Proteids . 2. Sugars, etc. ' 3 4. . » . . . 6 Questions 1. What are the uses of the lacteals ? 2. What nutrients are digested and absorbed in only one organ ? 3. Why must food be absorbed into the blood ? 4. What is necessary before most foods can be absorbed ? 5. What is the portal system ? The thoracic duct? 6. Which of the following pass into the lacteals, and which into the capillaries of the portal vein — sugar, peptones, emulsified fats? 7. Name the organs of absorption in the small intestine. 8. Water and salt need no digestion. Why? Where are they absorbed? 9. Through what large tube is the fat carried in passing from the lacteals to the veins? 10. Where do the capillaries that take part in absorption empty? 11. What provision is made for storing sugar so that it will not pass suddenly to the cells after a meal, but be given to them gradually? Note. — Food is assimilated, or changed into living matter (protoplasm), in the cells. 12. What changes take place in the composition of the blood in the lining of the stomach? In the small intestine? DIGESTION, CIRCULATION, AND ABSORPTION 281 References Hunter, Essentials of Biology. Chap. XXV. Hunter, Elements of Biology. Chap. XXVIII. Davison, The Human Body and Health (Advanced), pp. 98, 99, 108. PROBLEM XLVIII To study the general composition of blood. Materials. — Fresh frog's blood or blood from the finger. Slides, cover glasses, portable compound microscope, or com- pound microscopes set in various parts of the laboratory for inspection by the pupils under direction of the instructor. a. The Corpuscles Note. — Observe that the blood is composed of two com- ponents, solid bodies (corpuscles) and a liquid (plasma). Some of the corpuscles are disklike, and some globular and granular, while the plasma is the liquid in which the corpuscles float. Observations. — 1. What is the color of the corpuscles you most readily see ? What is their shape ? Note. — These are red corpuscles. 2. Do you find other corpuscles, — globular in shape and more transparent ? (Difficult to see.) Note. — These are white corpuscles. 3. What is the appearance of the plasma ? Conclusions. — 1. Do you think that the functions of the two kinds of corpuscles are the same ? That is, do special functions imply special structures? 2. Why does the blood appear red? 3. What have you already learned must be in the blood plasma? 4. What is an evident function of the plasma? Questions 1. What service do the red corpuscles render? The white ones? 282 DIGESTION, CIRCULATION, AND ABSORPTION 2. What is the use of fibrin ? 3. What is serum? 4. What is the composition and use of blood plasma? 5. What is the function of plasma? 6. What are the chief functions of blood ? Special Reports 1. The work of the white corpuscles in destroying disease germs. 2. The necessity of a liquid medium for carrying supplies to the cells (" citizens ") of the body, and for carrying away the waste. 3. The importance of coagulation. 4. The composition of the blood. 5. The life and work of Harvey. 6. The function of blood plasma. References Hunter, Essentials of Biology. Chap. XXVI. Hunter, Elements of Biology. Chap. XXIX. PROBLEM XLIX A study of the circulation of the blood. Materials. — Living frog, tadpole, or fish partly affected with ether, chloroform, or 1 % solution of chloretone, and mounted on a shingle having a i-inch hole bored in one end, over which is placed the web of the hind leg of the frog or the thin part of the tadpole's tail or a fin of a fish. Keep the specimen wrapped in a moist cloth, and the part observed moist. Or use a chick embryo of 36 to 72 hours. Open the egg under a saline solution (.7 per cent NaCl at 38° C.). Remove the germinal disk with small dissecting scissors and float it out in a watch glass. Use low power here, with both low and high powers as needed for the rest. a. Living Specimen Observations. — 1. Note a network of small tubes with mov- ing disks, partly obscured in the frog by many dark-colored, DIGESTION, CIRCULATION, AND ABSORPTION 283 irregular pigment cells. If you find the blood moving in reg- ular spurts in any of the tubes, note how often the " spurts " take place. (These tubes lead from the heart, and are called arteries.) FIG. 64. — Capillary circulation in the web of a frog's foot ; a, b, small veins ; d, capillaries showing corpuscles following one another in single series ; c, pigment cells in the skin. 2. Do the arteries remain of a uniform size ? If not, what becomes of them as you trace in the direction the blood flows ? (The tubes into which arteries divide are called capillaries, and connect the arteries with tubes called veins that commonly carry impure blood, and lead toward the heart.) 3. How does the blood flow in a vein differ from that in an artery ? 4. Do you notice any disklike bodies (red corpuscles) in the blood ? Are they numerous or few ? 5. Look for minute colorless bodies (white corpuscles). Conclusion. — Sum up your conclusions regarding the circula- 284 DIGESTION, CIRCULATION, AND ABSORPTION tion of the blood as shown on the web of a frog's foot, or tail of a tadpole, etc. Capillary Network FIG. 65. — Capillary network, showing connection of arteries and veins. b. Your Body Method. — Place a finger of your right hand on the artery of the left wrist, just at the base of the thumb. Count the number of pulsa- tions after you have been sitting quietly, after rising and again sitting, and after a little ex- ercise or light gym- nastics. (All stand for this phase of the exercise and try a " setting up " exercise for a half minute or so.) FJG. 60. —Diagram showing how the heart acts as a Jrva ion. — force pump. What is the pulse DIGESTION, CIRCULATION, AND ABSORPTION 285 Capillaries beat per minute when quiet ? What when lightly exercising ? What when more vigorously exercising ? Conclusion. — Write out your conclusions as to the effect of exercise on the heart action and thus of the pulse. Observation. — Press a vein in your wrist with one ringer. On side of ringer toward the heart empty the vein by just rubbing an- other finger along it. Does the blood flow back into the vein ? Rub the blood away from the heart, on other side of finger pressing the vein. Does the blood flow back ? Conclusion. — What is your conclusion concerning the structure and direction Lungs of blood flow in the veins ? c. Study of Chart, and Sheep or Beef Heart Method. — 1. Refer to any good chart of the cir- culation or to Figure 67 and find the heart, arteries, and veins. Also examine a sheep or beef heart or good model and note the four chambers, the valves, and the blood tubes connected to it. Observations. — 1. In what direction do arteries lead? Veins ? 2. Can you make out the heart to be a double force pump ? Study Figure 66. FIG. 67. — Plan of circulation of blood. 286 DIGESTION, CIRCULATION, AND ABSORPTION 3. Where does the right side of the heart send the blood ? The left ? 4. How do arteries end ? Veins begin ? 5. Do you find any special blood tubes running to tho liver? Note. — Much digested food absorbed from the small intestine must pass through the liver before it reaches the heart. Many impurities are taken out in the liver. Conclusion. — Trace the general circulation of the blood. d. The Circulatory System Observations. — 1. Try to fill in the following outline : — I. General function of circulation. II. Materials carried, their sources and destinations : — MATERIALS SOURCE DESTINATION 1 2. 3. 4. 5. III. Constituents of the blood, with their special functions (Report in tabular form.) 1. Plasma, a. b. c. 2. Corpuscles, a. b. IV. The circulatory apparatus and functions. 1. The heart. DIGESTION, CIRCULATION, AND ABSORPTION 287 2. The blood vessels. a. b. c. 3. The lymph and lymph vessels. Y. The course of the circulation. (Represent it by means of a diagram.) e. Use of a Tourniquet Observations. — 1. Study Figure 68, in order to learn where best to apply a tourniquet. Practice making and applying FIG. 68.— Regions where some large arteries lie near the skin. one made of a ruler or stick, pocket handkerchief or towel, and a pebble or any such solid. See Figure 69. 2. Practice finding the pulse in the ankle or wrist, and then press on the artery above these points until the pulse is stopped. Conclusion. — Where must a tourniquet be placed with reference to the cut and the heart (1) if a cut artery ? (2) Vein ? 288 DIGESTION, CIRCULATION, AND ABSORPTION Questions 1. Which are buried the deeper, — arteries or veins ? Why ? 2. Which is more com- pressible,— a vein or an artery ? 3. Should a person lean over a bowl when having nosebleed ? Explain. 4. Why are those who take little exercise liable to have cold hands and feet? 5. What keeps the blood moving between heart- beats ? 6. What are lacteals? Lymphatics ? 7. Why does too severe exercise hurt the heart ? 8. What effect have FIG. 69. — Showing how to apply a tourni- headache remedies on the quet, made by tiglitly twisting a hand- -, p , «•> kerchief so as to press a piece of wood against the brachial artery. 9- What are colds ? 1. 2. 3. 4. 5. 6. 7. cold.' 8. 0. body. Special Reports The effect of tobacco on the heart. How to treat a bruise. Explain the treatment. How to restore from fainting. The effect of alcohol on the heart. The best way to stop the flow of blood from an artery. A vein. How muscular exercise aids the heart. How best to treat colds. Explain "Cold is the best prevention of i. • The effect of work, pure air, and rest on the blood. Changes in the composition of the blood as it courses through the DIGESTION, CIRCULATION, AND ABSORPTION 289 10. The systemic circulation. 11. Lymph and its functions. 12. What is a tourniquet ? The portal circulation. References Hunter, Essentials of Biology. Chap. XXVI. Hunter, Elements of Biology. Chap. XXX. PROBLEM L Some changes in the composition of the blood. a. Absorption Observations. — 1. What is ready to be added to the blood from the stomach? Small intestine ? 2. What per cent of food that reaches the blood is absorbed by the villi of the small intestine ? 3. What nutrient ab- sorbed by the lacteals ? 4. What is the por- tal system ? Conclusion. — Sum up all the changes in the composition of the blood, due to absorp- tion. b. A Special Use of Plasma Observations. — 1. What part of the blood is able to pass through the walls of the capil- laries ? Note that it is now called lymph. 2. What is the reason for the process ? SHARPE'S LAB. MAN. — 19 FIG. 70.— Diagram of the capillaries uniting an artery and a vein. The plasma is passing through the walls of the capillaries to nourish the hody cells, after which some of it enters the mouths of the lymph vessels and the rest passes back to the capillaries. 290 DIGESTION, CIRCULATION, AND ABSORPTION 3. Study Figure 70. What does it show ? 4. If the cells might be called " citizens," compare with the city of Venice. Conclusion. — What are some of the changes that take place in the composition of the blood in the tissues ? c. The Liver Observations. — 1. Refer to Figure 63 in Problem XL VII. What have you learned passes through the liver ? Why ? 2. What are the functions of the liver ? Conclusion. — What changes then take place in the composi- tion of the blood in the liver ? Questions 1. Explain how the blood feeds the body. 2. What is the use of lymph vessels ? 3. How is the food absorbed from the small intestine ? 4. What is the portal circulation ? 5. Where does the oxidation of nutrients take place ? 6. What results when a candle or wood is oxidized ? 7. What is the function of the lymph ? 8. What is the function of the lymphatic vessels ? 9. What vessel drains the lymph from the remainder of the body? References Hunter, Essentials of Biology. Chap. XXVI. Hunter, Elements of Biology. Chap. XXX. Davison, The Human Body and Health (Advanced). Chap. XI. Eddy, Textbook in General Physiology and Anatomy. Hutchison, Applied Physiology. ADAPTATIONS FOR RESPIRATION AND EXCRETION PROBLEM LI A study of the organs and process of respiration. a. Organs of Respiration in Frog 1. LIVING SPECIMEN Note. — Keview Problem XXXVII, Section d. 2. DISSECTED SPECIMENS OB CHART, SHOWING THE LUNGS IN PLACE Observations. — 1. Examine the dissected frog. Open the frog's mouth and find a slitlike opening (glottis) just back of the tongue. Insert a glass tube or blowpipe and force air down a short windpipe (trachea) which branches shortly into other short tubes (bronchial tubes) that lead to the lungs. 2. How much larger are the inflated lungs than the unin- flated ones ? 3. Are the walls of the lungs elastic ? Do they look spongy ? Can you see cell-like places ? Are the lungs hollow ? Conclusions. — 1. Explain how the structure of the lungs affords a comparatively large area of moist membrane separat- ing the blood on the one hand with its contained gases from the air on the other. 2. In what part of the lungs should you be likely to find the air poorest in oxygen ? 3. Make a diagram of the respiratory system of a frog. Show just how it inhales oxygen and exhales carbon dioxide. 291 292 RESPIRATION AND EXCRETION b. Mechanics of Respiration 1. MOVEMENTS Observations. — 1. Note the movements of your body while breathing, both when breathing quietly and when breathing deeply. Is there an elastic rebound as the breath goes in or out? 2. Does the air leave the lungs without effort ? Conclusion. — Which movement requires the greatest effort, taking in the air (inspiration) or sending it out (expiration) ? 2. THE DIAPHRAGM Materials. — Small bell jar with opening at top for a 2-holed rubber stopper, sheet rubber tied over base of jar, with piece of chalk in the center of the rubber. Y-tube with toy balloons fastened to each branch of the Y and with the straight part passing through the stopper. When arranged as in Figure 71, the toy balloons will represent the lungs, or even air cells, the glass tube the trachea, the branches the bronchial tubes, and the glass jar the chest. Method. — Catch the knobbed place formed by the piece of chalk in the rubber sheet, and pull it downwards. Watch the effect on the toy balloons (lungs). Permit the membrane to return to place and ob- serve again. Or set the apparatus on a bowl, the outer diameter of which is slightly smaller than the inner diameter of jar. This will cause the rubber to be pushed to an arched position. Lift the apparatus from the bowl, and the rubber flattens to a position taken on inspiration. Observations. — 1. What is the effect on the size of the bal- FIG. 71. — Diagram to represent action of the diaphragm. RESPIRATION AND EXCRETION 293 loons when the rubber (diaphragm) is pulled down ? When relaxed ? 2. What is the position of the rubber in each case ? Conclusions. — 1. Is there more or less room in the bell jar (chest) when the rub- ber (diaphragm) is pulled down ? 2. Compare the ef- fect of the rubber with the function of the diaphragm in your body. (See chart or Figures for the loca- tion of the diaphragm.) 3. THE RIBS Materials. — Make a model like Figure 72 FlG> 72>~ Diasram showing action of the ribs, a, position during expiration ; 6, position during using a strip of wood inspiration. to represent the back- bone, and other strips to represent the ribs and breastbone. Use small nails to form loose joints at the corners. Use a cord for the diagonal. Method. — Hold the apparatus as in Figure 72 and pull the cord ed in the direction of the arrow. Note what happens. Observations. — 1. What change in the distance between ec (breastbone) and df (backbone) when de is pulled ? Note. — If cd and ef represent ribs, what does ed represent? 2. The ribs by their own elasticity bring the breastbone from the position b to the position a. Are the ribs fastened to the backbone with joints as in the apparatus ? Conclusions. — 1. What effect on the capacity of the chest when the muscles pull the ribs upwards and outwards ? 294 RESPIRATION AND EXCRETION Front, jyutmonaTy artery 2. What effect when the ribs by their own elasticity return to their original position ? 3. In what two ways do you now know the chest cavity may be en- larged ? 4. How does air get into the air cells of the lungs ? c. Process of Respiration in the Lungs Observations. — 1. How do air tubes end in the lungs ? 2. Why are these end- ings so thin-walled? 3: What does Figure 73 illustrate ? Conclusions. — 1. Just take place in the lungs ? here? FIG. 73. — Diagram to show respiration in the lungs. how does the process of respiration 2. Just what changes take place d. Cell Respiration Observations. — 1. What does Figure 74 illustrate? 2. What wastes are formed when food is oxidized at the cells? 3. What desirable results when food is oxidized? Note. — Observations 2 and 3 may be illustrated chemically as follows : — Starch + oxygen = carbon dioxide + water + heat + muscular energy.1 C6Hi005 + 6 O2 = G C02 + o H20 -f heat + muscular energy. 1 Heat and muscular energy are both energy resulting from the oxidation of what ? Where does the oxidation take place ? About 30% is muscular en- ergy, the remaining 70 % is bodily heat. RESPIRATION AND EXCRETION 295 Conclusions. — 1. What becomes of the oxygen taken in by the blood in the lungs ? 2. What is the use of the oxygen? 3. What is the purpose of cell respiration ? 4. What becomes of the wastes formed ? 5. What becomes of the heat and energy formed ? FIG. 74. — Diagram to show respiration of cells. e. Capacity of Lungs (Optional) FIG. 75. — Measuring the vital capacity of the lungs. The bottle was filled with water, which is being forced out by expir- ing the air from the lungs through the rubber tube slipped up into the mouth of the bottle kept under water in the pan. (Davison.) Materials. — Gallon bottle, cork, rubber tubing, and a two-gallon vessel as a pan or water container. Method.— Fill the bottle with water, invert in the two- gallon pan or container, re- move the cork, insert the end of the rubber tubing, fill lungs to their fullest capacity, and force as much air as possible into the bottle. Observations. — 1. What happens to the water as the air enters? 2. How much water flows from the bottle? What has taken its place ? Conclusions. — 1. How much air do you conclude came from your lungs ? 1 2. If, say, 100 cu. in. re- mained in the lungs, what is the capacity of your lungs ? 296 RESPIRATION AND EXCRETION Questions 1. What lines the respiratory tract? Its function? 2. Of what use is oxygen in the body ? 3. How do the air tubes end ? Of what use are the air cells ? 4. How may artificial breathing be produced? 5. Name some common diseases of the respiratory system. 6. What are adenoids? What results from them? 7. What are the signs of their presence ? 8. How does tobacco affect the respiratory system? 9. How does alcohol affect the respiratory system ? 10. How revive any one from drowning ? 11. What does a cell gain from oxidizing food? 12. In what two ways is the chest enlarged? 13. Why are deep breathing exercises valuable ? 14. Give some habits that impair the power of the lungs. Special Topics 1. Consumption and its prevention. 2. Bronchitis and its prevention. 3. Pneumonia and its prevention. 4. The effect of tight lacing on the respiratory organs. 5. The movements of the ribs and diaphragm in breathing. 6. Cell respiration. References Hunter, Essentials of Biology. Chap. XXVII. Hunter, Elements of Biology. Chap. XXXIII. PROBLEM LII A study of the products of respiration. Materials. — Limewater, test tubes, piece of cold metal or cold windowpane, thermometer, small candle, splint. a. General Tests Method a. — Breathe on a cold piece of metal or glass. What takes place? Conclusion? RESPIRATION AND EXCRETION 297 Method b. — Breathe on the bulb of a thermometer. 1. What are your observations ? Conclusions ? Method c. — Breathe through a glass tube into a test tube half filled with lime water. What takes place ? Conclusion ? Method d. — Place a small lighted candle in a bottle, and after the flame has gone out, insert a flaming splint. What takes place ? Observation. — Pour into the bottle two or three tablespoon- fuls of lime water, and shake it. What is the result ? Conclusions. — 1. What was formed by the burning candle ? 2. Will this gas support combustion ? Review note. — Carbon dioxide is produced by the union of oxygen of the air with carbon which may be either in candles, wood, coal, or the fats and carbohydrates stored in your body or in foods. 3. What goes on in your body, as indicated by the last two tests ? Method e. — Hold a tin cup half filled with cold water over a small burning candle so as not to interfere with the flame arid not so near as to heat the cup. What do you observe ? Conclusions. — 1. What is another of the results of oxidation of a candle ? 2. What similar process goes on in your body ? 3. Which is the more intense, — the heat of oxidation of the candle, or the heat of oxidation of the body ? In which case is oxidation the more rapid ? Which requires the greater supply of oxygen ? 4. What is the purpose of a draft in a stove or furnace ? How is the oxygen supplied for oxidation in the body ? Where does the carbon come from ? b. Air in Room Method. — Fill a large bottle with water, and take it into a room containing many people. Pour out the water. What is 298 RESPIRATION AND EXCRETION now in the bottle ? Test with a few tablespoonfuls of lime- water. What are your observations ? Conclusions. — 1. In what condition is the air in the room ? 2. What is your conclusion concerning the ventilation ? c. Exercise and Respiration Method. — Count the rates of breathing before and after rather vigorous exercise. What are your observations ? Conclusions. — -1. What effect on the temperature of your body ? Heartbeat ? Why so ? 2. Where does the necessary energy for vigorous exercise or work come from ? 3. Explain the effect of exercise upon the appetite ? d. Organic Waste Method. — Breathe into a clean bottle, cork it, and set it aside in a warm place for a day or two. Now uncork the bottle and smell the air in it. What is the result ? Conclusions. — 1. What is your conclusion ? Note. — An ill- smelling odor indicates the decay of organic matter. 2. Sum up your conclusions as to the wastes given off from the blood in the lungs. Questions 1. Where does the energy of locomotion come from ? 2. What are the objects of respiration ? 3. Sum up all the products of respiration. 4. What are the changes of air in the lungs ? 5. What are the changes in the composition of the blood in the lungs ? 6. What is meant by oxidation ? Results of oxidation ? 7. Trace the course of oxygen until it reaches the cells. 8. What does a cell gain by oxidizing food ? RESPIRATION AND EXCRETION 299 Special Reports 1. The importance of fresh air for general health. 2. Comparison of the human body or any animal body with a steam engine. 3. The source of energy in animals. 4. The relation between muscular exercise and respiration. References Hunter, Essentials of Biology. Chap. XXVII. Hunter, Elements of Biology. Chap. XXXIII. Davison, The Human Body and Health (Advanced). Chap. XIII. PROBLEM LIII JL study of ventilation.1 Materials. — A box of 7x10 inches base and 6 inches high placed on a side and having 4 half-inch holes bored in each end, and fitted with corks. Have a pane of glass to close the box. Place two candles in the box as shown in Figure 76. Method. — Light one of the candles so as to use up oxygen. The Candle will also give off FlG 75. — Showing arrangement of box with carbon dioxide, heat, glass front, for experiment in ventilation, and water. Kemove the (After Davison.) corks from one set of holes at a time, and observe the effects on the burning candle. a. General Study Observations. — 1. Place all the corks in. How long does the candle burn ? 1 Adapted from Davison. 300 RESPIRATION AND EXCRETION 2. Remove the two upper corks from one end. How long does the candle burn ? 3. Remove the upper corks from both ends. Result ? 4. Remove one upper and one lower cork from one end. Result ? Conclusions. — 1. Explain the result when all the corks are in place. 2. Explain the result when the upper corks in both ends are removed. 3. Explain the course of the air (oxygen) when the upper and lower corks at one end are removed. Which of the three trials is the most successful ? Why ? 4. Make cross-section sketches and explain the different trials as above. Use dotted lines and arrows to represent the course of the air. Draw a horizontal dotted line to repre- sent the level of the candle tip (person's head). Label inlet i and outlet o. b. Dust Method. — Allow only a beam of light to enter the room on a sunny day. Shake various articles near this beam. Gather a pail of clean snow and melt it. Let a pan of water stand un- covered on the window sill or other outer exposure. Observations. — 1. What is given off from the shaken arti- cles ? 2. Is the water from the melted snow clear and pure ? 3. What do you notice on the surface of the water ? Conclusion. — What is your conclusion ? Questions 1. How can you show that plants give off oxygen ? 2. Name some of the impurities of the air. 3. Why should people sleep with the windows open ? 4. How should you ventilate a room heated with a stove ? 5. Why should rugs be used in place of carpets ? RESPIRATION AND EXCRETION 301 6. Why is it healthful to have a pan of water on the radi- ator or stove ? 7. What is a ventilator ? Explain one. 8. How ventilate through the windows without causing a draft ? 9. How is your schoolroom ventilated ? 10. Why should a hat be well ventilated ? 11. Explain the advantage of using damp sawdust or tea grounds when sweeping. 12. What months are worst for hay-fever patients ? Explain. 13. What are the best ways for keeping dust out of the house ? 14. Which becomes dusty sooner, an unpaved or a paved street ? Explain. 15. Are there any special liquids to prevent dust in rooms ? In roads ? 16. Which is more cleanly, gas light or electric light? Explain. 17. In what ways does street sprinkling favor comfort and health ? 18. What part of your city or town is dustiest ? Least dusty ? Why ? 19. Explain the advantages of the vacuum cleaner. 20. Some of the advantages of traveling by boat ? 21. What effect have autos and bicycles in stirring up dust ? Preventive ? 22. The effect of burning gas or lamps on the air in a room ? 23. How can you tell when the air in a room is bad ? 24. Name some ways of avoiding drafts in ventilation. Special Reports 1. The need of ventilation. 2. Sweeping and dusting. 3. Hygienic habits of breathing. 4. Tenement houses and ventilation. 5. The black hole of Calcutta. 302 RESPIRATION AND EXCRETION 6. Ventilating systems. 7. Hay fever and its cure. 8. The comparative merits of plush and leather or leatherette for upholstering, so far as health is concerned. 9. The comparative merits of carpets and rugs. 10. The work of the street cleaning department. 11. What to do to prevent spread of fires in a building. 12. The public health laws of your state. 13. The work of the health department of your city or town. 14. Communicable diseases. References Hunter, Essentials of Biology. Chap. XXVIL Davison, The Human Body and Health (Advanced). Chap. XIV. Monthly Bulletin of the New York State Department of Health. State Health Bulletins. Bulletins of the Department of Health of cities and towns. Rensselaer, Martha von, " Practical Housekeeping." Cornell Univer- sity Reading Course, Series 1, No. 3, 1903. Northend, M. H., "A Fresh Air Sleeping Room." Suburban Life, March, 1909. Miiller, J. P., The Fresh Air Book. Ritchie, J. W., Primer of Sanitation. Prudden, M., Dr., Dust and its Dangers. Sedgewick, Municipal Sanitation. Westwood, E. H., " Sleeping in the Open." Pictorial Beview, April, 1910. Hendrick, B. J., " Chicago's Fight for Fresh Air." McClure's Maga- zine, August, 1910. SUMMARY V The nature and hygiene of some congestions or inflam- mations. (See Hunter, Essentials of Biology, page 394^ a. Nature Observations. — 1. Carefully note what is shown in Figure 77. What is the main difference shown between arterial capillaries (arterioles) in a normal state and when congested ? Note. — Whenever congestion or inflammation occurs, the RESPIRATION AND EXCRETION 303 muscle fibers in the walls of the capillaries are either relaxed or injured, thus permitting more blood to pass through them. 2. Try naming some of the common characteristics of con- gestion or inflammation, — color, appearance, feeling, etc. Conclusions. — 1. Just what do you understand is meant by the term ' congestion ' ? 2. What condition of the capillaries must be brought about in order to reduce congestions or inflammations ? b. Some Common Inflammations Observations. — 1. What name is given to congestions in the nasal cavity? In the pharynx? In the larynx? In the chest ? In the stomach ? In the intestine ? Ill FIG. 77. — A, diagram of circulation from artery through capillaries to vein of frog. B, diagram of circulation in congestion, showing dilatation of blood vessels and crowding of corpuscles. (After Warren.) 2. What are some of the symptoms showing congestions in these organs ? Conclusions. — 1. What must be the general appearance and condition of these parts of the respiratory and alimentary tracts when so influenced ? 304 RESPIRATION AND EXCRETION 2. Would such congested areas be more likely or less likely to be susceptible to the attacks of bacteria ? 3. What, then, is the main danger connected with conges- tions ? Note. — It is now understood that colds are infections, and that dampness and drafts are but favoring conditions for their development. c. A Common Cause (Advanced Work) Observation. — What are some of the symptoms of com- mon " colds " ? Note. — Colds start as active congestions, thus widening the arterioles with a consequent more rapid flow of blood, finally resulting in a more passive state, with white corpuscles thickly adhering to the internal walls of the capillaries. Conclusions. — 1. How must myriads of clinging white cor- puscles affect the size of the bore of capillary tubes ? 2. Show how these tubes now become gorged with blood. d. Summary of Hygienic Hints1 Avoid arterial dilation in inflamed areas : — a. In diarrheal conditions by, 1. Avoiding heavy meals. Why ? What effect on congestion ? 2. Light diet. Something easily digested and absorbed. 6. In colds by, 1. Avoiding chilling the skin. Why? Note. — Heat increases the size of the capillaries of the skin, while cold decreases it. What would become of the blood in the capillaries of the skin if it was driven out by sudden cooling ? 2. Keeping warmly clad. Why ? 3. Keeping sleeping rooms well ventilated but not too cold. 4. Discontinuing cold baths temporarily, if such had been the habit. Why ? 5. Avoiding all dampness. Why ? 6. Keeping the full share of the blood in the skin. What might be the effect if even the feet were permitted to become chilled ? 7. Breathing fresh a£r, but not at the expense of chilling the skin. 1 Adapted from Hough and Sedgewick, The Human Mechanism. RESPIRATION AND EXCRETION 305 8. Hot baths, hot lemonade, or other hot drinks when the cold is just starting. Why ? Note. — These avail little after the disease is well started. It then becomes a struggle between the body and the disease. 9. In general, avoiding all drugs, except as prescribed by a physician. 10. Moderately exercising the muscles, because of the following normal physiological effects : (a) Temporary relief of congestion. Why ? (&) Better regulation of body temperature. Why ? (c) Greater physical and chemical changes in the body and lymph. (d) Freshening the lymph flow to the cells. (e) Keeping up the regular work of the heart. (/) Keeping up the depth and frequency of the respiratory movements, and therefore better ventilation of the lungs. (0) Increasing the activity of the digestive organs and glands. PROBLEM LIV, PART I (Experimental) To study some of the functions of the skin of man. Materials. — Compound microscope, hand lens, ether or alco- hol, large glass jar, and two thermometers. a. Experimental Method a. — Touch the skin at several places with the point of your pencil. Observations. — 1. Do you find any place insensible to the touch ? 2. Are all parts equally sensitive ? Conclusion. — What is one function of the skin ? Method b. — Cool a large glass jar. Insert one hand in it, and close the rest of the opening by wrapping the wrist with a handkerchief or towel. Watch the inner surface of the jar for a few minutes. Observation. — Does anything collect on the inner surface of the jar? SHARPE'S LAB. MAN. — 20 306 RESPIRATION AND EXCRETION Method c. — Weigh yourself just before taking exercise in the gymnasium. Weigh yourself at the end of the period. Observation. — What is the loss in weight ? Why is there a loss, if any ? Conclusion. — What is another function of the skin ? Method d. — Wrap the bulb of a thermometer with a strip of cloth, and wet it with water of the same temperature as the room. Let it stand a short time near a thermometer with a dry bulb. Observation. — Read the two thermometers. Do they agree ? What difference do you note ? Note. — As water or any other liquid evaporates, it uses heat, which is taken from near-by substances. Conclusion. — What caused the wet thermometer to read differently from the dry one ? Method e. — Place a few drops of ether or alcohol on the back of the hand and note results. Observations. — 1. What happens to the liquid ? 2. What is the effect on the hand ? (What sensation ?) Conclusions. — 1. What do you conclude regarding the effect of evaporation on temperature ? 2. Where did the moisture come from that collected on the inside of the bell jar ? WThat is it called ? 3. What is given off at all times by the skin? 4. What is its function ? Method f. — Examine the palm of the hand or the inside of the fingers where they are ridged with a hand lens, and see if you can find very small pits (sweat or perspiration pores) on the ridges. Observation. — Where are the pores located ? Are there few or many ? b. Structure (Optional) Method g. — Study a prepared slide, showing cross section of the skin. Use low power objective, or study any good Figure. Observations. — 1. Find two layers of the skin, an outer (epidermis) and an inner (dermis). RESPIRATION AND EXCRETION 307 2. Do you find any elevations of the dermis that extend into the epi- dermis ? Describe one. 3. Note some coiled tubes (sweat glands) which lead to the surface of the skin. Do they seem to correspond in location with the openings seen with the hand lens ? Note. — The instructor may well here call attention to the hairs and oil glands. Conclusions. — 1. Where is the perspiration formed (secreted') ? 2. What is one of its functions ? 3. Is the skin a sense organ ? Explain. 4. Write a summary of the main functions of the skin. 5. Tell something of the structure of the skin. Questions 1. Why should much water be drunk daily ? 2. When do you perspire the most ? 3. Why should the skin be kept clean ? 4. What is the chief physiological use of clothing ? 5. Why is it necessary to bathe frequently ? 6. How does a corn differ from a blister ? 7. What effect have rubber shoes on the feet ? 8. How should you treat burns ? 9. State facts that show the skin gives off wastes. 10. Explain the function of perspiration. 11. Why is heat more oppressive in moist weather ? 12. What is the temperature of the healthy body ? 13. What may cause baldness ? 14. What is the cause and what the cure for dandruff ? 15. What is the relation of bodily heat to work performed ? 16. How treat cuts ? 17. Why should most people take a moderately cold bath daily ? 18. What is the effect of alcohol on the bodily heat ? 19. What is the use of a hot bath ? Cold bath ? 20. What care should be observed when swimming ? 21. Why is ammonia used in refrigerators or in cooling ? 22. Why never employ a doctor advertising to cure cancer ? 308 RESPIRATION AND EXCRETION Special Reports 1. The function of the kidneys. 2. The functions of the skin. 3. The care of the hair and nails. 4. Advantages of hot and cold baths. 5. Cause and cure of dandruff. 6. Influence of alcohol on the skin. 7. The relative values of cotton and wool for clothing. 8. Artificial ice. 9. The bodily excretions. References Hunter, Essentials of Biology. Chap. XXVII. Hunter, Elements of Biology. Chap. XXXIV. Davison, The Human Body and Health (Advanced). Chap. XVI. Eddy, Textbook in General Physiology and Anatomy. Martin, Human Body. Chap. XVIII. PROBLEM LIV, PART II (Summary) A final study of the changes in the composition of the blood as it passes through various organs of the body. a. Normal Changes Observations. — 1. Fill in the following tabulation : — INCOME OF BLOOD FKOM ORGANS OUTGO OF BLOOD TO 1. Alimentary Canal (^ from small in- testine) .... 2. Tissues (muscle, nerve, bone, etc., all living cells) . . 4. Lungs .... 5. Kidneys .... 6. Skin RESPIRATION AND EXCRETION 309 2. What should be the relationship between the income and outgo columns ? Try to prove it. Conclusions. — 1. Write a paragraph summing up all the nor- mal changes that take place in the composition of the blood. 2. What different bodily functions are involved in these changes ? b. A Special Change Observations 1. Study Figure 78. What is one function of the white corpus- cles ? 2. What happens concerning these cor- puscles in case of cuts, bruises, or splinters ? Conclusions. — 1. Why are the white corpuscles Of ten called Fm 78._Diagram of a capillary network, show- a kind of " Jack of all ing the white corpuscles creeping through the trades " ? walls of the capillaries to eat bacteria, causing o ™r •.!_ JT a boil at rn. 2. Write an addi- tional note on possible changes in the composition of the blood, due to disease or accident. Questions 1. Which of the organs listed in the table above are purely excretory organs ? Which partly so ? 2. What are excretions ? 3. What are the functions of the liver ? 4. What is the cause of boils ? 5. Give the cause of the changes that take place in the com- position of the blood in the muscles. 6. How does the life of one of the body cells remind one of the life of a small animal in a pond ? 310 RESPIRATION AND EXCRETION Special Reports 1. The bodily excretions. 2. Causes of changes in the composition of blood. 3. The cause of boils. 4. Changes in the composition of the blood. References Hunter, Essentials of Biology. Chap. XXVII. Hunter, Elements of Biology. Chap. XXXIV. Davison, The Human Body and Health (Advanced). Chap. XVI. SUMMARY VI1 A final comparison of human body cells with a com- munity, —physiological division of labor. a. Division of Labor Observations. — 1. Note the different varieties of cells shown in Figure 46, from various parts of the body. Why may they be called "tiny citizens of the body community7'? 2. Name some cells that belong to the body community that are not shown in the Figure. Conclusions. — 1. Show how the red blood corpuscles of the body may be compared to railroad men. Note. — Why canals instead of railroads in the body community ? 2. How may the digestive cells be compared with farmers ? Note. — Keep in mind the work of the farmer in converting crude soil into things suitable for man's consumption. 3. How may you compare the colorless or white blood corpuscles with soldiers and policemen ? 4. Show how nerve cells may be compared with governors and teachers. 5. Compare cells in the skin and kidneys with scavengers. 6. What may the muscle cells be compared to in a human community ? 1 The field work for Problem LVI, II, Sanitary Map, and Sanitation should now be started. RESPIRATION AND EXCRETION 311 7. Compare the ciliated cells of the windpipe with efficient housemaids. Observation. — Review your definitions of tissues and organs. Conclusions. — 1. Show how tissues and organs may be com- pared with companies and regiments of men. 2. Show how division of labor is illustrated in the human body. b. Special Questions 1. What advantage in each cell doing only a special piece of work instead of doing everything an animal needs to do, as in the amoeba ? 2. How does the efficiency of wild tribes of men compare with civilized men ? What is the main difference ? 3. What do we mean when we say "higher animals"? Just in what sense are they " higher " ? 4. Should men and women be educated to do the same work? 5. What is meant by the term " progress by specialization " ? 6. Show how equal work, as between men and women, is a violation of nature's law of progress, and would cause race degeneration. 7. What are tissues ? Organs ? 8. Name some tissues in the human body. Why may they be called " master tissues " ? 9. Define the following terms: "anatomy," "physiology," " hygiene," " biology." NERVES AND THEIR CONTROL PROBLEM LV A study of the nervous system, reactions to stimuli, and habit formation. a. Anatomy Materials. — Frogs preserved in alcohol or formalin, scissors, forceps, hand lens, charts showing nervous system of man. (Optionally use prepared specimens of the nervous system of frogs or of mammals.) Note. — The nervous system of man and animals is primarily a device for making locomotion safe. Observations. — 1. Open the abdomen of a frog and remove the organs found in it. Find some white cords (nerves) near the back. 2. Trace some nerves into the legs, dissecting away the muscle. 3. Carefully remove the upper half of skull, and find some white lobes (brain). 4. Cut away the skin, muscles, and upper half of the back- bone, so as to trace a large nerve in it (spinal cord). 5. Refer to a chart showing nervous system of a frog, and notice the branching. Conclusion. — Compare the nerve cords with a telegraph sys- tem. What corresponds to headquarters ? (Study the func- tion of the brain in any good text.) Observations. — 1. Note the white elongated hemispheres of the forebrain, or cerebrum. The two anterior projections of the cerebrum are called olfactory lobes. Where do these lobes seem to lead ? Wrhat is the meaning of the term 'olfactory ' ? 312 NERVES AND THEIR CONTROL 313 2. Just back of the cerebrum find the mid-brain. The dorsal part is enlarged into two large lobes, known as optic lobes. Are there branches leading from them ? Where do they lead ? Note. — The term 'optic' refers to sight. 3. How do the optic lobes compare in size with the cerebrum ? 4. The hindmost part of the brain is known as the medulla. To what does it join posteriorly ? Conclusion. — Write a paragraph tell- ing what you can of the nervous system of the frog. Observation. — Study Figure 79. The cell much branched is known as a neuron, or a unit of the nervous system. The brain and spinal cord contain many millions of them. Conclusions. — 1. If a branch from one should end in a muscle, in which direc- tion would messages travel through it ? 2. If a branch from a neuron should end in the sensitive part of the tongue or tip of the finger, in what direction would messages travel through it? •--^Dendritea •Cell Body —Neuraxon -Medulla . Node ofHanvier ---Neurilemma Nerve-ends 7> FIG. 79. — Diagram of a neuron or nerve unit. b. Reactions 1. REFLEX Observations. Note. — Reflex action is involuntary action tak- ing place before the brain has had time to aid or interfere in any way. 1. Feign a blow at a person's face. Result ? 2. Tickle the inside of the nose with a feather. Result ? Conclusion. — What do you judge is the especial reason for each of the reflex actions just noted ? 314 NERVES AND THEIR CONTROL 2. VOLUNTARY REACTION Observations. — 1. Send any whispered word around the class. Take the time at instant of starting the word, by the instructor, and also again when received, to determine time of transmission. Divide time of transmission by number in the class. What is the average time of voluntary reaction ? 2. Let members of class stand and touch hands. The in- structor will now send a touch signal, as a long and short pres- sure of fingers, to imitate a telegraph signal. Get the average reaction time as before. How does it compare with the first or ear reaction ? Conclusions. — 1. How do voluntary reactions differ from in- voluntary ones ? 2. How do ear reactions compare with touch reactions ? c. Frog Observation. — 1. Refer back to your study of the frog. What reactions have you noticed? Try to classify them, into voluntary and involuntary. Conclusions. — 1. Tell how the reactions of the frog compare with those of man; that is, which do you think has the better nervous system? 2. Show how the note at the beginning of the problem may apply to any animal. d. Sources of Knowledge and Action Note. — " The mind is a collective term for the operations of the nervous system." Observations. — 1. Touch the back of the hand with a pencil point. 2. Close the eyes and place on different parts of the tongue several substances, as sugar, vinegar, salt, weak ammonia, etc. What part of the tongue is most sensitive to each? 3. Test your hearing by determining how far off the tick of a watch can be heard. NERVES AND THEIR CONTROL 315 4. Determine the farthest distance you can identify any certain letter in a book. Also nearest distance. Conclusions. — 1. Write a paragraph telling all you can con- cerning your lead pencil. Just how have you obtained your information ? 2. Are you able to rely on your impressions; that is, do they vary from day to day? Note. — "The work of science is to find out in some degree the real nature of the universe." Your knowledge of science must come through your own senses. The ultimate end of science is the regulating of human conduct. " Seeing true means thinking right. Right thinking means right action." Wrong thinking brings wrong action, which causes misery, which is nature's protest against this wrong action. 3. Touch your finger to a hot stove. Show just how the result explains the above note. 4. Explain the statement, " There is no alleviation for the woes of life except absolute veracity of action, the resolute facing of the world as it is." 5. Explain the statement, "As food must be formed into tissue, so must perception pass over into action " ; that is, are sensations for any other purpose than proper action? e. Habits 1. BENEFICIAL Observations. — 1. Recall your experience in learning to write. Compare with your ability to do so at present. What has happened ? 2. Try doing a difficult gymnastic feat. As nerve cell after nerve cell (neuron after neuron, see Figure 79) sends out orders to the muscles, do they seem to be able to handle the situa- tion in improved ways ? Explain. 3. Do you suppose the neurons of a child just learning to walk find it easy to send out just the right orders to the muscles? Explain your answer. 316 NERVES AND THEIR CONTROL 4. Do you now find it so easy to walk that you can also think of distant or other things at the same time? If so, of what advantage is it to you? 5. When watching a group of people learning to do anything in concert, as drills of children, etc., or of soldiers, how did the first rehearsal compare with the last ? Note. — As soldier after soldier, or child after child, became better able to do his part, so neuron after neuron of the brain and spinal cord became better able to do their parts, until finally there is habitual action. 6. Explain the following story: "A practical joker saw a discharged veteran carrying his dinner home ; he suddenly called out, ' Attention'; whereupon the veteran instantly brought his hands down, dropping his dinner in the gutter." Conclusions. — 1. How are habits formed? Illustrate your answer, using the term "nerve cell." 2. Mention one advantage of a good habit, as walking, etc. Observations. — 1. Suppose a man must concentrate his mind on just how to walk, or to digest, or to dodge an unexpected blow, or to resist falling, etc. How would it affect the safety of his life ? 2. Mention as many actions of your body as you can that tend to safety and comfort of life. Are the habits of content- ment and self-control of any value ? Conclusions. — 1. Write a paragraph on the increased effec- tiveness and power acquired through good habits. 2. Is it easy to break a habit ? Explain your answer. 3. Explain the statement, " Life is but a tissue of habits." 2. HARMFUL Observations. — 1. Boil a pipeful of tobacco in a pint of water, Put the resulting solution into a small aquarium containing a tadpole or a small goldfish. Results ? 2. Draw the smoke from 5 or 6 cigarettes through water in the bottle as shown in Figure 80. Pour the liquid into a small aquarium containing a tadpole or goldfish. Results ? NERVES AND THEIR CONTROL 317 Conclusion. — What is the result of tobacco poison on the nervous system ? Observations. — 1. Why do life insurance companies consider even "moderate drinkers" as an "extra risk"? \ FIG. 80. — Experiment to show how tobacco affects the nerves, m is a tube through which the air is sucked from the bottle nearly full of water. This draws smoke from the lighted cigarette through the tube down into the water. The poison in the smoke from six cigarettes was thus drawn into the water which was later poured into the jar with the fish, putting it to sleep in one half hour, and finally killing it. 2. What is the recognized effect of opium on the sense organs ? Conclusions. — 1. What do you think of the reliability of impressions from the sense organs when they are affected by alcohol, opium, or tobacco ? 2. Explain the statement, "Every failure in the sense organs, every form of deterioration of the nerves, shows itself in reduction of power." Observations. — 1. Study the following statement: "The hell to be endured hereafter, of which theology tells, is no worse than the hell we make for ourselves in this world by habitually fashioning our characters in the wrong way. Could the young , 318 NERVES AND THEIR CONTROL but realize how soon they will become mere bundles of habits, they would give more heed to their conduct while in the plas- tic state. We are spinning our own fates, good or evil, and never to be undone. Every smallest stroke of virtue or of vice leaves its never-so-little scar. The drunken Rip Van Winkle, in Jefferson's play, excuses himself for every fresh dereliction by saying, ' I won't count this time.' Well ! he may not count it; but it is being counted none the less. Down among his nerve cells and fibers the molecules are counting it, registering and storing it up to be used against him when the next temptation comes. Nothing we ever do is, in strict scientific literalness, iviped out. Of course this has its good side as well as its bad one. As we become permanent drunkards by so many separate drinks, so we become saints in the moral, and authorities in the practical and scientific spheres, by so many separate acts and hours of work. Let no youth have any anxiety about the upshot of his education whatever the line of it may be. If he keeps faithfully busy each hoar of the working day, he may safely leave the final result to itself. He can with perfect certainty count on waking up some fine morning, to find himself one of the compe- tent ones of his generation, in whatever pursuit he may have singled out." — JAMES, Psychology. Are habits formed sud- denly ? Are we always conscious that habits are being formed ? 2. Man is a bundle of appetites. What relation should his appetites bear to his better judgment ? Conclusions. — 1. Show that it is foolhardy to permit of any lack of perfect self-control. 2. Explain the statement, "There seems no possibility of improving our race except as the young are led to see the man- liness and dignity of self-control." Questions 1. Explain the statement, "One by one the little records within the brain cells (neurons) build up our lives and our characters) and determine our habits of action and of thought." 2. Why do employers favor boys who do not use tobacco? NERVES AND THEIR CONTROL 319 3. Why will not railroads employ even " moderate drinkers" ? 4. Why is an idler in the third grade likely to be an idler in the sixth ? 5. Why is a high school drone quite likely not to become a capable college student ? 6. Explain the statement, "Sow an act and reap a habit j sow a habit and reap a character.77 7. Why is it important that correct habits be formed early in life? 8. Explain the following : " The chains of habit are generally too small to be felt till they are too strong to be broken." Special Reports 1. Necessity of food, fresh air, and rest. 2. Necessity of good or right habits. 3. The waste of bad habits. 4. Self-control vs. appetite, 5. The habit of using headache powders and patent medicines. 6. The value of regular habits of work, exercise, and rest. References Hunter, Essentials of Biology. Chap. XXVIII. Hunter, Elements of Biology. Chap. XXXV. James, Psychology. Chap. X. Howe, S. H., Habit Formation and the Science of Teaching. Gulick, L. H., " The Will To Be Cheerful." World's Work, July, 1908. Gordon, Dr. H. L., The Modern Mother. Gulick, L. H., Control of Mind and Body. Hope and Browne, A Manual of School Hygiene. McComb, Samuel, "Alcoholism, Its Causation and Its Arrest. Every- body"1 s Magazine, April, 1909. — " Worry, Its Cause and Cure." Harper's Bazar, January, 1910. " Nervousness, A National Menace." Everybody's Magazine,~Feb- ruary, 1910. Walton, L. L., Why Worry ? Johnston, W. A., " What Science Has Done for the Child." The De- signer, March, 1910. PERSONAL AND CIVIC HYGIENE PROBLEM LVI A study of personal and civic hygiene. Note. — Disease germs are bacteria, or sometimes protozoa, that develop in the body and set free poisons. Nearly all that attack us come from the bodies of sick people. Therefore, we should endeavor to destroy all that come from such sources. I. HOW BACTERIA MAY ENTER THE BODY Materials. — A dozen sterilized Petri dishes, containing nu- trient gelatin. Observations. — 1. See that they have been kept well cov- ered. Label them 1 to 12. Set aside No. 1, labeled " not ex- posed," then in a temperature of about 70° F. Examine it for results after a day, two days, three days. 2. Sweep a corner of the room, thus stirring up a little dust. Open dish No. 2 and expose it to the air for half a minute. Set it aside and observe it daily. 3. Touch the gelatin of No. 3 with the tip of a lead pencil which has previously been moistened in the mouth. Set it aside and observe it daily. 4. Touch the gelatin of No. 4 with the tips of the fingers, that have not been recently washed in soap and water. Set it aside and observe it daily. 5. Moisten the gelatin of No. 5 with water. Set it aside and observe it daily. 6. Moisten the gelatin of No. 6 with milk. Set it aside and observe it daily. 320 PERSONAL AND CIVIC HYGIENE 321 7. Touch the rim of a public drinking cup to the gelatin of No. 7. Set it aside and observe it daily. 8. Cause a house fly to walk across the gelatin of No. 8. See that the legs of the fly touch the gelatin at several places. Set it aside and observe it daily. 9. Touch the gelatin of No. 9 with dust from the street or roadway. Set it aside and observe it daily. 10. Note. — Eeserve the rest for second trials, if necessary. The above cultures are known as inoculations, as they were inoculated ; that is, germs were planted in a favorable growing place. 11. Tabulate your results as follows : — 1 2 3 4 B 6 7 8 9 g j M a &, H *| 0 o | w g K g 3 PH |H ^ « * & £ p2 2 5 H br g Q h U H H C * Date of appearance of colonies . . . First appearance of colonies, number, size, color, etc. Changes in size, color, etc., at the end of the trial .... Note. — Each spot on the gelatin represents a colony of bac- teria, or mold, which has developed from germs originally placed there. Conclusions. — 1. From what different sources may bacteria enter the body ? 2. Explain just how bacteria may enter the body from the different sources enumerated in your last answer. Note. — It has been recently proved that cracked earthenware dishes, SHARPE S LAB. MAN. 21 322 PERSONAL AND CIVIC HYGIENE or pottery, may harbor germs in the cracks in such numbers as to be a dangerous means of introducing them into our bodies. 3. Note that such diseases as smallpox, scarlet fever, and consumption may be taken by breathing the germs of these diseases in with air, and so are called contagious diseases. The healthy thus acquire the diseases by coming near the sick or tuberculosis lockjaw pneumonia typhoid sore throat diphtheria sleeping sickness boils leprosy grippe malaria FIG. 81. — Germs that cause various diseases. Highly magnified. (After Davison.) where they have been. Malaria and such diseases are non- contagious, as they require the bite of an insect or at least the breaking of the skin in order to introduce the disease. They are also infectious, as they are caused by tiny parasites which feed on the human body as a host. Such diseases as diabetes and insanity are noninfectious as they are not caused by parasites. 4. What disease germs may enter the body from drinking water or milk ? 5. What might happen if the excreta from a typhoid patient was thrown out near the sources of streams that supply villages lower down with water ? 6. Explain how such excreta may be disinfected. PERSONAL AND CIVIC HYGIENE 323 7. Suppose a person with tuberculosis spits in public places. What is quite certain to be the result ? 8. Explain why it is criminally careless for any one to spit in public places, on walks, etc. Note. — Pocket waterproof sputum cups are now manufac- tured and should be used by all consumptives. They may then be burned or disinfected by carbolic ^TJ acid or lysol. Under no circumstances should the ^MIH^L ^f^SC'^i^E^ sputum be allowed to dry up. Why ? 9. How do you suppose all the disease germs that are in dust originally got there, such as of consump- tion, pneumonia, catarrh, meningitis, measles, in- FIG. 82. — Germs of tuberculosis from the fluenza, and scarlet fever ? spit of a """"""P*™- Is there much spitting in your town or city ? Where, if any ? 10. Since dust about human habitations must inevitably con- tain germs un,der present conditions, what are some of the best means of keeping them out of our bodies ? Note. — The dust in public buildings may be kept down by using sawdust damp- ened with water, to which has been added -j- pint of kerosene and a tablespoonful of formalin. Why add formalin ? 11. Why should feather dusters not be used in dusting? Note. — A cloth dampened with water containing a little kero- sene makes a most excellent duster. Why use kerosene? 12. Why may carpets be detrimental to health ? 13. How may the leaves and covers of a book become car- riers of the germs of some diseases ? WThy should all publicly used books be at least covered ? 14. May germs enter the body through breaks in the skin ? What causes the soreness of any ordinary cut ? 324 PERSONAL AND CIVIC HYGIENE II. A SANITARY MAP, AND SANITATION Note. — This work should be started as field work several weeks before it is taken up in the class room. Observations. — 1. Get a map of the neighborhood, village, borough, or township. If none can be obtained, sketch one as best you can. Mark with a star any houses where any trans- missible diseases have been, or are at present. Indicate the number of cases with a figure. Also indicate the nature of the disease with an initial as, *2T would mean, two typhoid cases at this place. Get your information through neighborhood inquiry, or from quarantine placards, otherwise through pub- lic officers, such as health officials, either local or state. Which sort of disease is most common ? 2. Mark on the map the location of any cesspools, or sewage emptying into streams. 3. Locate any marshes or stagnant ponds. Also any open rain barrels, or tin cans, etc., which may hold rain water. Do any of them contain any wigglers or mosquito larvae ? 4. Locate any garbage dumps. Also any garbage pails that are commonly left open. Are there any places where the garbage is left in the back yard ? Are children permitted to play about such places ? 5. Locate any manure heaps near stables. Also any unclean stables, either for horses or cows. If there are any manure heaps, find out whether any measures are taken to kill maggots, or the young of flies. What, if any ? 6. Locate any public restaurants where there is an exces- sive number of flies about, and permitted on the food and in the building. Are such places cleanly ? 7. Locate any dry closets or outhouses. Also piles of decaying vegetable matter. Also any places where the soil is commonly polluted by the excreta of human beings being permitted to remain on the surface for any length of time. Note. — It is said that barefoot children running about on the polluted soil of some of the regions of our Southern states, as PERSONAL AND CIVIC HYGIENE 325 well as Porto Rico and the Philippines, contract a certain disease. What ? 8. Locate any public places where there is much spitting on the floors or walks. Is the place uncleanly in other respects ? Are there flies about ? 9. Locate any stores exposing any foods — especially fruits and vegetables — for sale, so that dust and flies may readily come in contact with them. Are these foods also handled by those who are marketing ? 10. Locate any public fountains with drinking cups. 11. Locate any railroads. Note. — Any railroads using the or- dinary means of disposing of excreta become like open sewers or worse. Why ? All such excreta should be collected in retain- ing vessels and disposed of at various stations along the route. 12. Locate any excessively dusty streets. Also any that are unduly shady or continually damp. Note. — The work of the above tabulation may be most profitably done by dividing it among different members of classes, — especially if the district studied is very large, or populous. Conclusions. — 1. Does there seem to be any connection between the sanitary condition of the district and the number and kind of diseases found? 2. Can you suggest any improvements and give your reasons for them ? 3. Try to plot a curve showing variations in the death rate due to any of the diseases you have located on the map. Get the data for twelve months from the local or state health department. Try to sum up all the different factors concerned and see if you can account for any variations shown during the year. (See next section for instructions for plotting curves.) III. INFANT MORTALITY CURVE Method a. — Let the alternate vertical lines of a sheet of cross-section paper represent the months of the year in order. 326 PERSONAL AND CIVIC HYGIENE At the top of the left vertical line but one write Jan. ; the fourth, Feb., etc., or rule paper as in Figure 83. Let the spaces between the heavy horizontal lines represent 50 deaths. Kefer to mortality tables published by Departments of Health of various cities and get such data as is represented in the following table,1 which was taken from one published in the Annual Report of Department of Health of the city of New York, 1908, p. 841 (except data for flies, which came from a supplemental report of the Merchants' Association of New York). DATE JAN. 4 FEB. 1 MARCH APRIL 8 MAY 9 MAY 23 JUNE 20 Diarrheals under five .'"'.... ... 32 26 36 51 62 49 86 Under one year . . 262 254 279 275 284 268 268 Mean temp. (Fah.) . 38.2 28.9 32.2 49.2 53.8 66.4 72.6 Average .... Prevalence of flies . 0 0 0 0 0 0 250 DATE JULY 4 JULY 25 AUG. 8 SEPT. 5 OCT. 3 Nov. 7 DEC. 5 Diarrheals under five . . „ . ;v •• 202 424 327 244 192 72 39 Under one year . i , 354 508 469 382 311 217 208 Mean temp. (Fah.) . 79.5 80.6 81 69.4 61.1 44.6 43.1 Average .... Prevalence of flies . 2000 1900 2200 200 400 0 0 i Courtesy of Dr. W. H. Allen, Director of the Bureau of Municipal Research, New York. PERSONAL AND CIVIC HYGIENE 327 Now since there were 32 deaths the week of Jan. 4, we take such a part of the January column measured toward the right on line OX as 4 days is a part of 31 days and make a tiny cross, and measure up on the line OY ff of the height of the first square and make another tiny cross. The first tiny cross lo- cates a vertical line, or imaginary line, while the second cross Y JAN. FEE MCH. APR. MAY JUNE! JULY AUG. SEPT. OCT. NOV. O * X FIG. 83. — Infant mortality curve, a, prevalence of flies; 6, diarrheals under five years ; c, deaths under one year ; d, mean temperature. Scales 1 c.m. = 50 deaths 1 c.m. = 200 fly prevalence 1 c.m. = 10 degrees 1 c.m. = 15 days locates a horizontal line. At the place of crossing of these two lines make another tiny cross. This cross indicates that there were 32 deaths of children under 5 years of age during the week of Jan. 4, 1908, in New York city. Next locate the vertical line representing Feb. 1 and the horizontal line valued at 26, and locate a second crossing point. Continue in this way, and connect all the tiny checks made with an evenly curved line. This is called a " curve " and in this case might be called a " diarrheal curve." Now take the second line of data from the table and locate another curve. 328 PERSONAL AND CIVIC HYGIENE (The various curves may be represented in different colored pencils, or by differently broken lines, as in Figure 83.) Locate the temperature curve in the same way. However, since the temperature numbers do not run so high, it is wise to allow a large square's distance on the vertical line 0 T, as representing 10 degrees. Thus continue to locate as many curves as is desired, taking care not to intermingle so many, however, as to make difficult reading. Observation, — What months show the highest mean temper- ature ? The greatest prevalence of flies ? The highest death rate under one year ? Five years ? Conclusions. — 1. What months have the most favorable tem- perature for the development of bacteria in milk ? What extra care should be taken with the milk supply (a) when milking ? (6) when in transit to customer ? (c) when in hands of customer ? 2. What does the "prevalence of flies" curve show (a) as to comparison with mean temperature ? (b) prevalence of diarrheal diseases ? (c) deaths under one year ? 3. What special precautions should be observed by all and especially mothers with babies under five years as to (a) milk supply ? (b) food of any description ? (c) presence of flies ? 4. Tell some of the ways by which you could aid in helping to reduce the terrible mortality of babies during the summer months, especially in the large cities. Note. — In 1908, 15,000 babies under one year of age died in New York city alone from improper preparation and care of food. Method b. — Using the above as a model, refer to any mor- tality tables l you may be able to get and plot similar curves and write out any conclusions you may be able to make. Of course the most valuable one for your purposes would be from data furnished by your own local Department of Health. If such cannot be obtained, use those published by your State Department of Health, or of any other city or state. 1 Such tables as given on p. 33, Bulletin Merchants' Association, New York, " The House Fly at the Bar," are good. Also study the curves plotted in the same bulletin. PERSONAL AND CIVIC HYGIENE 329 Try to decide just how you would go at it in order to im- prove conditions, or show your neighbors who may not know as much about the matter as you have found out. IV. OTHER MORTALITY CURVES (FOR ADVANCED STUDENTS) Observations. — 1. Use monthly or yearly reports of the department of health from any source, as, for example, The Report of the New York City or New York State Departments of Health. Try to plot curves as in the preceding section for other causes of death, as, for example, measles, scarlet fever, diph- theria, croup, meningitis, pneumonia, diarrheal diseases, con- genital debility, etc. 2. Which sort of disease is most prevalent during the year? In summer ? Winter ? Spring ? Autumn ? Conclusions. — 1. Try to account for the greater prevalence of certain diseases at certain times of the year. (Note tem- perature, food, milk, water, flies, exposure, sanitation, etc.) 2. What means would be most effective in reducing such death rates ? Specify in detail for each particular disease. 3. Suggest how you might cooperate with the Board of Health. 4. Comment on the following statement : " Six hundred thousand infants under two years of age end their little span of life yearly, while millions of children fail to reach their best physical development because their mothers and fathers understood not how to care for them in the light of science — with more knowledge at least half the number of babies could be saved and the physical standard raised immeasurably." — Household Education League. V. PREVENTION OF INFECTIOUS DISEASES 1. In section I we have learned First : that disease germs come from the bodies of the sick in excreta, sputum, etc. ; 330 PERSONAL AND CIVIC HYGIENE Second : careless people are scattering gerrns about, so that they finally reach the bodies of the well. 2. It would therefore seem wise that, if we wish to prevent these germs from entering our bodies, we must First : immediately destroy the germs that may be in the excreta of the sick ; Second : prevent disease germs that are being scattered about carelessly from entering the body, as well as reduce the scattering as much as possible ; and also, Third : develop in the body a power to fight these germs (immunity) if they should happen to enter the body. a. Destroy Germs from the Sick 1. DISINFECTION OF SPUTUM AND EXCRETA 1. How have you learned germs may leave the bodies of the sick ? (See section I.) 2. How have you learned such germs may be killed ? (See Prob. XXIII, c). What have you learned concerning the value of heat, sunlight, drying, and certain chemicals such as corrosive sublimate, carbolic acid, lysol, and formalin? Chloride of lime, milk of lime, and cresol are also very good. Note. — Any germ killers, such as those just named, are known as disinfectants. The wastes from the bodies of the sick may be received in receptacles, and disinfected by adding an equal bulk of 5 % formalin, lysol, or corrosive sublimate. Let the waste matter stand several hours before disposing of it. Why ? 3. If germs are from the nose or mouth, the sputum or mucus containing them should be received in small pasteboard cups, or a handkerchief. These should all be burned as soon as practicable. Carbolic acid or lysol may be added in case it is not convenient to burn them. Under no circumstances per- mit sputum from those diseased to dry. Why not ? PERSONAL AND CIVIC HYGIENE 331 2. QUARANTINE (HOME) Observations. — Note. To quarantine is to separate those suffer- ing from contagious disease from the well. The sick are sent to hospitals or detained at home until well. 1. Why should houses with diseased inmates be placarded ? 2. What benefit from permitting sunshine to enter the rooms of quarantined people ? 3. Show why heavy curtains or carpets should not be allowed in the room. 4. Should clothing, carpets, etc., be taken from the room without boiling or disinfecting them ? Explain. 5. Would it be well to sweep the room before the sick are removed ? Explain. How should the room be dusted ? Conclusion. — Write a paragraph telling how to quarantine a person in a house. Observations. — 1. Suggest how the room may be disinfected after the patient recovers. Note. — One of the best means is, first, to stop all cracks, etc., with wet paper. Put one pint of pure formalin in two quarts of water. Evaporate it with heat. Or, wring out cloths from the solution and hang them on lines in the warm room. Keep the room closed twelve hours, then open to fresh air and sunshine as much as possible for a day or so. 2. Why should one's hands be washed with soap and water after handling a patient or his clothes ? 3. Why should a patient's body and hair be cleansed with soap and water after recovery ? Conclusion . — Write a paragraph telling how to disinfect a room and a person after quarantine. :. . ,3. SHIP QUARANTINE (ELLIS ISLAND) Observations. — 1. Why is New York city often called "America's Front Door"? 2. Why are incoming ships met in the harbor by a health officer ? 332 PERSONAL AND CIVIC HYGIENE 3. Why are steerage passengers taken to Ellis Island and special inspections made ? Conclusion. — Write a paragraph telling how ship quarantine is of special value in destroying germs from the sick. b. Prevent Germs from entering the Body Considerations. — 1. Study Figure 84. Is there any good reason for keeping flies away from food ? FIG. 84. — Showing how house flies carry disease germs from putrid matter to babies. (Courtesy of The American Civic Association.) 2. Why is the common fly called the 'typhoid fly'? 3. Explain the benefits of boiling and filtering water. Of pasteurizing milk. 4. Why should there be no such things as public drinking cups, towels, combs, etc. ? 5. Why should we be especially careful and not permit ourselves to be bitten by such insects as mosquitoes, fleas, and bedbugs ? 6. Explain just why sputum should not be permitted in public places. 7. What are the reasons for sewage disposal ? 8. Why should railroads be especially careful in disposing of the wastes from the human body ? Conclusion. — Write a paragraph or two telling what you can of the different ways of preventing germs from entering our bodies. PERSONAL AND CIVIC HYGIENE 333 c. Development of Immunity Note. — Immunity is such a state of the body that disease germs are comparatively harmless. It depends on the power of the blood and other fluids of the body to kill germs. Observations. — 1. Are there any advantages to the body because of plenty of fresh air, good food, rest, and exercise ? 2. Review the functions of the white corpuscles of the blood. 3. What effect has alcohol on the white corpuscles? 4. What are antitoxins? Note. — An antitoxin is a sub- stance that prevents poisons commonly developed in the body from the growth and action of disease germs from harming the body. They are given to prevent such diseases as diphtheria, rabies, etc. Name others. 5. How are antitoxins given? Note. — Whenever germs in antitoxin or vaccine are introduced into the body artificially, the person receiving the germs is said to be inoculated. 6. What is meant by vaccination? Note. — Smallpox, cholera, anthrax in cattle, and hydrophobia are being success- fully fought by means of vaccination to-day. 7. Explain the modern treatment for consumption. Conclusion. — Write a paragraph, summing up all you know as to the different means of bringing about immunity in the body. d. Work of the Board of Health " The greatest problem of the health official is the influential citizen who insists on his right to live like a hog, and be a menace and a nuisance to all his neighbors." — An American Health Official. Note. — All citizens should obey their instructions implicitly and aid Health Boards to the best of their ability. 1. See that certain laws are enforced to prevent causes of sickness and spread of diseases. What diseases ? 2. Placard all houses with contagious diseases, quarantine the inmates, and later disinfect the house. Why ? 334 PERSONAL AND CIVIC HYGIENE 3. See that the garbage is buried or burned, and sewerage properly disposed of. Why ? 4. Prevent the sale of unhealthful milk and foods. Why ? 5. Provide for a supply of pure water. Why? e. Health Creeds and Leagues Observations. — 1. See if you can justify or condemn the fol- lowing statements of Health Creeds : — 1. Eat moderately. Meat no more than once a day. Fletcherize. 2. Drink pure water. About 8 glasses a day, between meals. No water at meals. 3. Keep in fresh air as much as possible. Breathe deeply. If you cannot walk, at least bundle up and sit in the sun. 4. Plenty of fresh air in the sleeping room. Have sitting room win- dow lowered at least one foot. 6. Bathe or wash every day in as cold water as one can well stand. 6. For adults, drink no milk. 7. Eat plenty of fat, to fight disease germs. 8. Have change of occupation. 9. Avoid intoxicants, which destroy the cells that fight disease germs. 10. Keep your temper./— II 1. Eight hours' sleep. 2. Sleep on right side. 3. Keep bedroom window open all night. 4. Have no mat at bedroom door. 5. Bedstead not against wall. 6. Bathe in morning at body temperature. 7. Exercise before breakfast. 8. Eat little meat, and that well cooked. 9. For adults, drink no milk. 10. Eat plenty of fat. 11. Avoid intoxicants. 12. Daily exercise in open air. 13. No pet animals in living rooms. 14. Live in country, if you can. 15. Watch the three D's— drinking water, damp, and drains. PERSONAL AND CIVIC HYGIENE 335 16. Have change of occupation. 17. Take frequent and short holidays. 18. Limit your ambitions. 19. Keep your temper. — SIR JAMES SAWYER. 2. Write to Dr. Irving Fisher, of Yale University, asking the address of your state secretary of the American Health League. Ask his aid in forming a local league. 3. Form a local league in your school. Model your plat- form something after the following : — I AM A MEMBER OF THE American Hfealtlj Heague T TENCE. I believe in fresh air, sunshine, moderate eating of pure ^ ••• food, kind words, radiant cheer, and beautiful thoughts. I believe in assisting in every way possible to spread the idea of public health, both in governmental and in personal functions — thereby prolonging life, increasing human endeavor, and making easy the pursuit of happiness. — Ben La Bree, Jr., Ohio Secretary of the League. 4. On the basis that at any one moment there are at least 3,000,000 people in the United States seriously ill, half of which illness is preventable, will you write a letter to your Congressman, urging the establishment of a United States Bureau of Health ? Study the following reasons and rewrite them in your own language : — To stop the spread of typhoid fever through drinking sewage-polluted water of interstate streams. To enforce adequate quarantine regulations, so as to keep out of the country plague and other similar pestilences. To supervise interstate common carriers, in so far as without such supervision they prove a menace to the health of the traveling public. 336 PERSONAL AND CIVIC HYGIENE To have a central organization of such dignity and importance that departments of health of states and cities will seek its cooperation. To influence health authorities, state and municipal, to enact uniform legislation in relation to health matters. To act as a clearing house of state and local health regulations and to codify such regulations. To draw up a model scheme of sanitary legislation for the assistance of state and municipal health officers. To gather accurate data on all questions of sanitation throughout the United States. To reduce the death rate. Questions 1. Why should dish cloths and towels be frequently scalded and sun-dried ? 2. Why should individual combs, towels, brushes, and drinking cups be used ? 3. Why should all fruits exposed for sale be kept covered ? 4. Why are oranges and bananas safer fruits when bought from a street vender than such fruits as apples, grapes, and pears ? 5. Why is the common practice of du-sting clothing in a Pullman car a dangerous one ? 6. Why are the so-called tourists' sleepers more sanitary than the ordinary Pullmans ? 7. Refrigerators should be frequently scalded out and washed with some antiseptic, as washing soda. Explain. 8. Give one sanitary reason for cooking foods. 9. Why should fruits eaten raw or with the skins be thoroughly cleansed? 10. What clothes most need the laundry, from the stand- point of health? 11. Why are there more intestinal troubles contracted in summer than in winter, while riding on railroad trains ? 12. What is one of the important uses of hydrogen peroxide ? 13. Why should city streets be flushed with an antiseptic water, instead of being swept ? (Chlorine water is good.) PERSONAL AND CIVIC HYGIENE 337 14. Why should there be a United States Bureau of Health f 15. "It is within the power of man to cause all parasitic diseases to disappear from the world.7' — PASTEUR. Comment on this statement. Special Reports 1. The great white plague. 2. What health is worth to us. 3. Personal hygiene. 4. Civics and health. 5. Health creeds. 6. The American Health League. 7. Quarantine. 8. Principles of sanitation. 9. Boards of health. 10. The development of immunity. 11. The life and work of Pasteur. 12. The bubonic plague. 13. Bacteria in daily life. References (Also see Problem XXIII) Hunter, Essentials of Biology. Chap. XXIX. Hunter, Elements of Biology. Davison, The Human Body and Health (Advanced). " The Great White Plague." City or State Health Officers. Fisher, Irving, "A Department of Dollars vs. a Department of Health." McClure's Magazine, July, 1910. Bjorkman, "What Health is Worth to us." World's Work, March, 1909. " Milk and its Products as Carriers of Tuberculous Infection." Cir- cular 143, Bureau of Plant Industry, U. S. Department of Agriculture. Hall, " What is to Become of your Baby ? " Cosmopolitan Magazine, April, 1910. "Sleeping Outdoors for Health." Country Life in America, May, 1909. Household Hygiene. Library of Home Economics, Chicago, 1907. Gulick, Mind and Work. "Malaria." Outing Magazine, May, 1909. " Alcoholism. Its Causation and its Arrest." Everybody's Magazine, April, 1909. SHARPE'S LAB. MAN. — 22 338 PERSONAL AND CIVIC HYGIENE Personal Hygiene. Library of Home Economics, Chicago. Home Care of the Sick. Library of Home Economics, Chicago. " Pure Milk and Human Life." Success. March, 1909. Allen, Civics and Health. "The Man of Perfect Health." World's Work, July, 1909, Chicago. Ritchie, Primer of Sanitation. . Morrison, " The Transmission of Disease by Money." Popular Science Monthly, January, 1910. Stevens, E. L., "The Next Move in School Supervision — Hygiene." World's Work, July, 1908. Lewis, "The Warfare Against Tuberculosis." Review of Reviews, September, 1908. Sadler, The Cause and Cure of Colds. Creelman, " Is Typhoid to be conquered at Last ? " Pearson's Maga- zine, December, 1909. "Our Duel with the Rats." (Economic Value, Bubonic Plague or Black Death, etc.) McClure's Magazine, May, 1910. (Good.) Rogers, James F., Life and Health. Chappell, F. A., "The House Fly — Man Killer." Pearson's Maga- zine, June, 1910. Bardswell and Chapman, Diet in Tuberculosis. Monthly Report of New York State Department of Health, Albany, N.Y. (or that of your own state). Weekly Report of the Department of Health of New York City (or your own city). Fisher, Irving, "National Vitality." Senate Document No. 676, Vol. Ill, 60th Congress. Banks, The Problems of Youth. Bevier, I., The Healthful Farmhouse. Brown, L. N., Scientific Living or Prolonging the Term of Human Life. Clarke, J. H., Vital Economy, or how to conserve your Strength. " Sanitary Drinking Cups." Bulletin, Kansas Board of Health, No. 3, 1909. Dorr, R. C., "A Fighting Chance for the City Child." Hampton's Magazine, July, 1910. Hutchison, Preventable Diseases. "The Doctor of the Future." Ladies' Home Journal, Novem- ber, 1909. The Conquest of Consumption. "Fat and its Follies." Cosmopolitan Magazine, February, 1910. Jewett, F. G., The Body and its Defenses. PERSONAL AND CIVIC HYGIENE 339 Latham and Garland, The Conquest of Consumption; an Economic Study. Morrison and Hilditch, "Does Money Carry Disease?" Literary Digest, March, 1910. Metchnikoff, E., The Prolongation of Life. The New Hygiene. ' "Rats as Pests.1' Farmers' Bulletin No. 369, U.S. Department of Agriculture. Sadler, W. S., The Science of Living, or the Art of Keeping Well. Overlook, M. G., How to protect the Health of the Working People. White, F. M., " The Occupation and Exercise Cure." Outlook, March, 1910. Curtis, E., Nature and Health. ^ Andrews, L. R., The White Peril. Burton-Fanning, F. W., The Open Air Treatment of Pulmonary Tuberculosis. Dorset, M., "Some Common Disinfectants." Farmers' Bulletin No. 345, U. S. Department of Agriculture, 1908. Godfrey, The Health of the City. Mason, W. P., "A Plea for Wider Sanitary Science Knowledge." Science, 29, February, 1910. Otis, Dr. E. O., The Great White Plague. Veiller, L., Housing Reform : a Handbook for Practical Use in Ameri- can Cities. Frankland, Mrs. P., Bacteria in Daily Life. Bashore, H. B., Outlines of Practical Sanitation. , Shaw, E. R., School Hygiene. Dock, L. L., Hygiene and Morality. Richards, Helen M., Euthenics, the Science of Controllable Environ- ment. Tenner, Philip, Education in Sexual Physiology and Hygiene. SUMMARY VII A summary of the causes and prevention of disease — personal and civic hygiene. I. THE CAUSES OF DISEASE 1. The work of parasites. (But one in forty die of old age.) Bacteria mostly. a. Infectious. (1) Contagious. 340 PERSONAL AND CIVIC HYGIENE (a) Consumption. (&) Smallpox, (c) Scarlet fever. (2) Noncontagious. (a) Yellow fever. (6) Lockjaw, (c) Typhoid. (d} Malaria. ',, • 6. Noninfectious. (1) Alcoholism. (2) Diabetes. (3) Insanity. (4) Cancer. 2. How germs enter the body. a. Breathing. b. Drinking cups. c. Pencils, fingers on books, etc. d. Food. 3. How tuberculosis may enter the body. a. With food or milk, — through walls of the intestine, thence to lungs in the blood. 6. With the air. 4. How typhoid germs enter the body. a. With food. 6. By flies on food. c. Milk. d. With water. Surface waters in shallow wells. 5. Alcohol. a. Weakens cells that fight disease. 6. Causes diseases of liver, kidneys, and heart. II. PREVENTION OF DISEASE Note. — Over 100,000 people lose their lives yearly by reason of germs. 1 . Destroy germs by : a. Boiling excreta from bowels and kidneys of persons suffering from contagious diseases. 6. Adding 4 % solution of formalin to excreta of the above. c. Putting the sputum of the sick in a cloth, or in boxes, and burn. d. Killing off the flies. e. Quarantine. PERSONAL AND CIVIC HYGIENE 341 /. Disinfecting rooms with 1 % carbolic acid, sunlight, and formalin. g. Disinfecting persons and their clothing. 2. Stop germs from entering the body by : a. Keeping flies away from food. b. Drinking from clean vessels, — pasteurize them as well as the milk and water. c. Keeping off mosquitoes, fleas, and bedbugs. d. Burning the sputum from patients. e. Filtering the water /. Disposing of sewage. g. Avoiding alcohol. h. Using individual drinking cups at public drinking places. 3. Develop in the body a substance which kills harmful germs by : a. Good food, rest, air, exercise, and sunlight. b. Antitoxins, — as against diphtheria, etc. c. Vaccines, for smallpox, hydrophobia, etc. SUMMARY VIII A summary of some biological processes in organisms, with special reference to reproduction, heredity, and hy- giene. a. The Flower Considerations. — 1 . What is the principal reason for the existence of any flower ? 2. What is produced by a complete flower? 3. What is the function of pollen ? Of ovules ? Of stamens ? Of pistils ? 4. Explain Figure 85. What does it show ? Note. — The cell in the pollen grain which grows into the pollen tube is known as the sperm cell. The cell in the ovule which fuses with the sperm cell is called the egg. When these fuse they form a single cell, — the fertilized egg. The egg immediately begins to develop (see Prob. XXVI, a), to form a minute prophecy of the future plant, which is called the embryo. This stops growing when the seed is ripe, in zones with a winter climate or a dry season, to again grow and develop when proper conditions of temperature and moisture are present. Conclusions. — 1 . Does there seem to be any reason for the fusion of the sperm cell with the egg? Note. — The two cells being different, may it be the case that each cell supplies the other with something that it lacks ? 342 PERSONAL AND CIVIC HYGIENE 2. Study Figure 86. Note that the end of the pollen tube containing the sperm cell is about to unite with the egg. FIG. 86. — Showing beginning stage of fu- sion of germ cells in cotton plant. (After Duggar.) P, pollen tube passing through the micropyle, and carrying a single sperm cell. E, egg. Note. — The sperm cell is thought to furnish the egg cell with a renewal of vigor, so that it will now actively de- velop to a mature plant. Otherwise it would stop, after reaching the period of growth represented by its condition in the ovule before fertilization. b. Protozoa Considerations. — 1. What is the simplest method of reproduction in such a simple-celled animal as a paramcecium ? 2. Will this method suffice for any length of time ? 3. What must happen to prevent the species from dying out? Note. — Conjugation is a term which may be used to denote either a temporary or permanent fusion with another individual. PERSONAL AND CIVIC HYGIENE 343 4. Find out just what happens when conjugation takes place. (Study charts or Figures or text.) Conclusions. — 1. Does there seem to be any reason why reproduction does not go on indefinitely by simple division ? Note. — "A freshening by the introduction of new vigor seems to be necessary from time to time." — ELECKEL. 2. Then why should Protozoa conjugate, or "trade experiences"? Note. — In conjugation of paramoacia the traveling nuclei serve as male traveling nuclei, while the nuclei remaining serve as female standing nuclei. When the fresh nuclei have been formed, they separate. The two new rejuvenated cells have once more acquired the power of renewed activity and also of the ability to propagate by division for a time, or until this power is exhausted, when conjugation must again take place. c. Metazoa 1. FISH Observations. — 1. Procure some fresh milt (sperm) of any fish most conveniently at hand, as from the nearest state or government fish hatchery. Also get some unfertilized eggs freshly ''stripped " from the body of the female. Place some of the unfertilized eggs in a clean bowl, as a glass finger bowl, and pour over them some of the milt or sperm. Set the bowl aside in a moderate temperature. (This is known as artificial fertilization.) Which are evidently the larger, sperm or eggs ? Which are the most motile ? (Examine some with a compound microscope.) 2. Place another lot of eggs in another bowl, and set aside with the first lot, but unfertilized. 3. Watch both lots for a few days. Which evidently increase in size ? 4. Has fertilization evidently taken place in one lot ? Explain your answer. Note. — In nature the ova (spawn or eggs) of fishes are usually deposited in the water in various hidden places on the bottom. The milt or sperm is poured over them by the male, and the eggs are left to develop with little or no care. 5. Do you think that such habits would result in much care of the young ? 6. Note. — The eggs of most sharks and such fishes are retained within the body of the mother until they are hatched. 7. Why should eggs be deposited in large numbers when they are laid in the water ? 8. Why are eggs fewer in number when they are fertilized within the .body of the mother, and afterwards laid ? 344 PERSONAL AND CIVIC HYGIENE Conclusions. — 1. Should you think there would likely be more or fewer eggs if they are not only fertilized within the body of the mother, but also hatched there ? 2. Explain whether better care is shown when eggs are deposited in the water to be fertilized and hatched, or when such processes take place within the body of the mother. 8. Which should be the larger because of contained food, — eggs that are laid, or those that are hatched within the body of the mother ? Note. — When any young are hatched within the body of the mother, they soon use up the food yolk of the egg, and thereupon develop a special set of blood tubes connecting with those of the mother, through which they get their food supply. 2. BIRDS Observations. — 1. Break a hen's egg into a saucer. Note a small cir- cular spot somewhat different from the yolk in color. Note, — This is the so-called germinal layer, and locates the real tiny egg. The yolk and the white constitute food for the growing embryo. 2. Has the embryo evidently developed much by the time the egg was laid? 3. Since the fertilized egg cells of birds are deposited outside of the body, can you see any reason for a shell ? 4. Why would it not be well that birds lay their eggs before the eggs are fertilized ? Do such animals as fishes and frogs lay eggs with shells ? Where are the eggs laid, and in what numbers ? 5. Compare the ovary of a bird with that of a flower. What likenesses do you find ? What differences ? Conclusions. — 1. What are the main differences in the process of fertilization of a bird's egg and the egg in the ovule of the lily ? Note. — The sperm cell of the male bird is very minute and is provided with a lash to whip itself along. 2. Why are eggs necessarily larger than sperm ? Which most readily admit of independent movement, sperm or egg ? Note. — We here find a fine example of physiological division of labor ; on the one hand con- jugating cells must be very motile and consequently minute, so that they may meet in such a liquid as water, where they are commonly liberated (examples : water plants, ferns and mosses, frogs and most fishes, etc.); and on the other hand, they must be so supplied with food that the young embryo may be provided for until it is able to shift for itself. These two requirements are here evidently met by a physiological division of labor between the two conjugating cells. One cell, called for convenience the PERSONAL AND CIVIC HYGIENE 345 sperm cell, is much reduced in size so as to be correspondingly very active and motile ; while the other, called the egg, has the food yolk stored up in it, with a consequent increased size, which prevents more than very slight independent movement, if any. 3. Can you distinguish between sexes among Paramoecia ? Lilies ? Note. — Along with differences between the sexes for purposes of division of labor, such as noted above, we note other secondary differ- ences between them creeping in, so that we may readily recognize male and female individuals. We readily distinguish a male bird from a hen. Note the differences between a peacock and a peahen. Give other ex- amples among higher animals. 3. VARIOUS MEANS USED BY SPERM CELLS IN REACHING EGGS (OPTIONAL) Observation. — Fill in the following tabulation, wherever possible : — METHOD EXAMPLES Plants Animals Conjugation Ciliated cells in water Pollen and wind Pollen and closed flowers Pollen and insects Motile pollen . .... Archegonium and motile sperm as of fern Pistil or pollen type Body tubes of Metazoa Artificial means d. Heredity " Nature loves variety, so that the best will survive. She has never yet made two eggs or two sperm cells exactly alike." — JORDAN. 346 PERSONAL AND CIVIC HYGIENE Observations. — 1. It is matter of common observation that individu- als are much like their parents. Children inherit race characteristics, and the young of roses are the same sort of roses, of salmon the same sort of salmon, and of Indians the same sort of Indians. We all agree that a rose does not produce a fern, or a fish a frog. 2. It is also a matter of common observation that individual peculiari- ties and deficiencies suffice to distinguish one rose, or fish, or person from another. Did you ever know two persons having the same color of eyes, hair, and skin ; the same form of nose and ears, character of thumb prints, etc. ? Conclusions. — 1. If the above observations are true, where have these peculiarities originated ? Do children or offspring commonly show traits of both parents ? 2. If so, how must these traits have been transmitted to the embryo ? Must they not have existed in the germ or sex cells ? Observations. — 1. Could the Arab raise swift horses if he had con- stantly mixed draft horses in the herd ? 2. Could Mr. Burbank produce fine fruits by mixing various plants indiscriminately ? Note. — The fine work of the horticulturist depends on selection and fixing of variations produced by cross fertilization be- tween rather closely allied plants. 3. What do you imagine might be the characteristics of a fruit re- sulting from the pollen of the plum being allowed to fertilize the ovules of the apricot ? Note. — Mr. Burbank has succeeded in producing such a fruit as would result from this process, called the plumcot. Such fruits are not always permanent, however, as they tend to revert (go back) to one or the other type. 4. What do you imagine might commonly be the result if a weak, sickly plant or animal should be crossed with another which might even be quite healthy ? Note. — Culled sheep, feeble, loose-jointed, and other- wise very poor in quality, have been bred, resulting in producing a still worse type of sheep, although it could be clearly seen they were Hamp- shire sheep. Conclusions. — 1. What is necessary in order to improve races and stocks ? Would it do to select poor parents ? 2. Why do farmers select the best ears of corn for seed ? What is the real reason ? 3. How are fast trotters developed by horse breeders ? 4. A man remarked : "I have drunk whisky every day for thirty -five years, and I don't see but what I have as good a constitution as the aver- age man of my age. I was never drunk in my life.1' His eldest child had perfect health, the second was of a remarkably nervous temperament, PERSONAL AND CIVIC HYGIENE 347 while the third, a young lady of seventeen, was epileptic and had always had poor health. May the father's habits have had anything to do with these facts ? 5. Can you think of any instances where families have a tendency to gout, consumption, or epilepsy ? Is there any noticeable effect on the children ? Note. — While these diseases may not be inherited, yet it is no longer doubted that the tendency to acquire them, or a weakness in such respects, may be transmitted. 6. What general conclusions can you make concerning the necessity of good general health of future fathers and mothers, either plant or animal ? e. Hygiene Note. — Since the inheritance of vigorous qualities of father or both parents may be impaired or totally destroyed, it would seem wise to con- sider how such qualities may be kept at their best, for the happiness of individuals and the good of the race. Considerations. — 1. What conditions lower the vitality of the body ? 2. What habits are injurious to the body ? 3. Name some germ diseases that are very harmful to the race. Note. — Some germ diseases are especially difficult to fight, particularly those producing blood poison. 4. How may disease germs enter the body? (See Prob. LVI, I.) Note. — Any opening in the body, or even a break in the skin, may permit the entrance of most deadly germs. 5. What might happen to the egg if disease germs should be carried to it with a growing pollen tube ? Conclusions. — 1. What part of a flower would be most probably seri- ously injured by bacteria should they attack it ? Explain. Note. — The sexual organs of all forms of life are very delicate, more so than even the eyes, ears, and nostrils. 2. Why should all living things exert great protective oversight of any- thing concerning the future of the race ? 3. Is it wise to use public drinking cups, towels, napkins, etc. ? Ex- plain. 4. Even if germ cells are not killed by the action of bacteria, their future development will be most certainly seriously crippled. Many cases of idiocy, insanity, epilepsy, etc., are undoubtedly due to diseased germ cells. 5. Study the reports in the monthly bulletins of the new State De- partment of Health. What do you conclude regarding the prevalence of 348 PERSONAL AND CIVIC HYGIENE disease germs ? Explain why great caution should be exerted in using public wash basins, bedding, unclean hands, knives, forks, pencils, pipes, etc. 6. Should any form of life be permitted to reproduce its kind, if there is any likelihood of either parent being diseased ? Explain. 7. Show how a large percentage of blindness may be produced before birth. 8. Write a paragraph on the necessity of proper food, exercise, rest, and recreation, especially with reference to heredity. Questions 1. What is the purpose of food yolk in eggs ? 2. Why does President D. S. Jordan say, t; Nature loves variety "? 3. Upon what does the fine work of the horticulturist depend ? 4. What has Mr. Burbank done for mankind ? 5. What precautions are exerted by farmers in selecting seeds ? 6. What is meant by heredity ? 7. How may disease germs enter the body ? 8. Why is the subject of heredity of so much importance ? 9. Why are children's games that require contact of hands very dan- gerous ? 10. What is one of the most common causes of blindness ? 11. Show how it is dangerous for one to handle the eyes, ears, nose, or other sensitive organs of the body. 12. What is likely to be the effect of the use of alcohol as a beverage by parents on their children ? 13. Tell of the great importance of controlling mind and body. 14. What have good thoughts to do with good health ? 15. Explain meaning of the following: " The great perpetual battle of life is the warfare waged against self." Special Reports 1. The everyday things one does to shorten life. 2. Scientific living, or the prolongation of human life. 3. Sleeping outdoors for health. 4. The importance of good thoughts, food, and exercise. 5. The occupation and rest cure. 6. National vitality. 7. The greatest social evil. 8. Hygiene and morality. \ PERSONAL AND CIVIC HYGIENE 349 9. Explain and make a special report upon the following : — " Thousands of homes are wrecked, tens of thousands of lives are ruined, and hundreds of thousands are made unhappy because the home-keepers of our country have no training in the greatest of all professions, the ' profession of home making and motherhood. ' Only through such edu- cation can present domestic difficulties be solved, and the modern home contribute all that it should to happiness and well-being." — Household Education League. References Fisher, Irving, "National Vitality, — Its Wastes and Conservation." Extract National Conservation Commission. Senate Document No. 676, Vol. Ill, 60th Congress, 2d Session. Banks, The Problems of Youth. 1909. Beach, "The Everyday Things one does to shorten Life." Pearson's Magazine, August, 1909. Brown, Scientific Living, or prolonging the Term of Human Life. Health Culture Co., New York, 1910. Dillon, "A New Way to Save Men." (Out-of-door Work for Con- victs.) The Delineator, March, 1910. D'Enville, Gulick, et al., "Sleeping Outdoors for Health. " Country Life in America, May, 1909. Gulick, Control of Mind and Body. Hopf, The Human Species, considered from the Standpoint of Com- parative Anatomy, Physiology, Pathology, and Bacteriology. Knight, Hygiene for Young People. Le Bosquet, Personal Hygiene. American School of Home Eco- nomics, Chicago, 1907. White, "The Occupation and Rest Cure." Outlook, March, 1910. Lyttleton, Training of the Young in Laws of Sex. Morrow, Social Diseases and Marriage. The Young Marts Problem. Educational Pamphlet No. 1,. American School of Moral and Sanitary Prophylaxis, New York. Hall, The Biology, Sociology, and Physiology of Reproduction, also Sexual Hygiene. Lee, H., "The Havoc of Prudery." Pearson's Magazine, Nov., 1910. Howard, "A Plain Explanation of the Greatest Social Evil." Pear- son's Magazine, May, 1910. Davenport, C. B., Eugenics. Reports of State Boards of Health, etc. Pyle, W. L., A Manual of Personal Hygiene. 350 PERSONAL AND CIVIC HYGIENE SUMMARY IX A summary of procedure in case of accidents and emer- gencies. Note. — About 10,000 people annually die for lack of quick aid. The first half hour is the most important. 1. Fainting. Lay the patient flat on the floor. Admit plenty of fresh air, Sprinkle cold water on the face. Give hot milk or water. 2. Intoxication. Empty the patient's stomach by giving a tablespoonful of mustard in warm water. Follow with two or three cups of strong coffee and put him to bed. 3. Fits. No effective remedy. Keep the patient from injuring himself. Put a handkerchief between his teeth to prevent him from biting his tongue. 4. Convulsions. Put the patient's feet and legs in hot water, and apply cold water to his forehead. Give a dose of a cathartic. 5. Sunstroke. Apply cold water on head, neck, and chest, and give "ice pack." Why? 6. Heat Exhaustion. Give the patient hot coffee, and put him to bed. 7. Suffocation. Fresh air and artificial respiration. Friction and hot coffee. 8. Clothing on fire. Wrap the patient in a coat or a blanket. Roll him over and over on the ground. Apply a dilute solution of soda, and smear vase- line over the burns. Get a physician at once. 9. Burns or Scalds. By means of cloths, apply carron oil (1 pint of limewater added to 1 pint of linseed oil shaken), vaseline, kerosene, and soda solution. If burned with acids, use soda ; if with alkalies, use vinegar. PERSONAL AND CIVIC HYGIENE 351 10. Frostbite. Rub the parts with snow or ice water, in a cold room till they tingle ; then in a warm room. 11. Cuts and Nail Punctures. Cause the wound to bleed freely. Wash it with turpentine, or 5 % solution of carbolic acid. Bind it with clean cotton. 12. Bruises. Apply a cloth wrung out of hot water, changed every two or three minutes, or use cold water as above. 13. Nosebleed. Throw the head back, put broken ice to the back of the neck. Close the nose and breathe through the mouth. 14. Choking. Strike the patient between shoulder blades, with his head down. Have him eat bread and potatoes to surround jagged object causing the choking. 15. Poison Bites and Stings. Apply a tourniquet between the wound and the heart. Cut the wound and cause it to bleed freely. Apply crystals of perman- ganate of potash. Give whisky to keep up the heart action. Bathe stings in dilute ammonia or soda solution. 16. General Poisons. (8000 deaths annually.) Give the patient an emetic of two tablespoonfuls of table salt in a glass of warm water, or a pint of warm water, or tickle his throat with a feather. 17. Special Poisons. a. CARBOLIC ACID. Give a tablespoonful of Epsom salts in glass of warm water, then a pint or so of milk, then a cup of coffee. 6. AMMONIA OR POTASH. Lemon juice or weak vinegar. c. ARSENIC. Give the patient an emetic, and then olive oil. d. POISONOUS PLANTS WHEN EATEN. Emetic, then Epsom salts. e. POISON IVY. Wash at once with soapsuds. Apply cloth soaked in equal parts of alcohol and water, with as much sugar of lead as will dissolve in it. 352 PERSONAL AND CIVIC HYGIENE 18. Sprains and Strains. Immerse the part in hot water or cold water, changed often. Massage a joint by rubbing toward the heart. Carefully ex- ercise it unless the ligaments are torn. 19. Particles in Eye. Look down and turn the eyelid back over a pencil. Bathe the eyes in weak boracic acid. A. List of common medicines every family should own, especially whan not within ready reach of a physician : — •1. Bottle of mustard. 7. Koll of antiseptic cotton. 2. Carron oil. 8. 3. Baking soda. 9. 4. Vinegar. 10. 5. Turpentine. 11. 6. 4 % carbolic acid. Roll of antiseptic linen. Permanganate of potash. Ammonia. Boracic acid. B. Contents of an emergency case : — 1. Cold cream. 2. 1 yd. cheese cloth. 3. Roll of adhesive tape. 4. Bicarbonate of soda. 5. Boracic acid. 6. Seidlitz powder. 7. Absorbent cotton. 0. 1 oz. bottle of : — a. Peroxide of hydrogen. b. Ammonia. c. Tincture of iodine. d. Spirits of camphor. e. Essence of peppermint. Card of safety pins. 10. Pair of scissors. Special Topics Using the above topics as subject matter, ask the pupils to explain just why any particular procedure is valuable in any particular case. Try to get the "reason why." References Moody, C. S., "Backwoods Surgery and Medicine." Outing Maga- zine, July, 1910. Northend and Purdy, "Summer Camp Dangers." Good Housekeep- ing, June, 1910. Warwick, F. J., First Aid to the Injured. UNIVEESITY OF CALIFORNIA LIBRARY, BERKELEY THIS BOOK IS DUE ON THE LAST DATE STAMPED BELOW Books not returned on time are subject to a fine of 50c per volume after the third day overdue, increasing to $1.00 per volume after the sixth day. Books not in demand may be renewed if application is made before expiration of loan period. MAR 30 1931 HI JUN* 60tn-7,'29 I 207635 £>4- THE UNIVERSITY OF CALIFORNIA LIBRARY