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A Guide for the Study of Animals

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An instructional manual for secondary-school biology that promotes an ecological approach to animal study, favoring brief investigations of many species to illustrate general biological principles rather than exhaustive type studies. It supplies practical classroom and laboratory exercises, field-trip forms and observation prompts, specimen lists, and clear definitions of anatomical terms and insect orders, alongside guided studies of common organisms such as grasshoppers. The guide stresses combining hands-on work with reference readings, highlights economic and applied topics including sanitation and agriculture, and recommends adapting fieldwork and assignments to local conditions and available time.

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Title: A Guide for the Study of Animals

Author: Worrallo Whitney

Frederic Colby Lucas

Harold Brough Shinn

Mabel Elizabeth Smallwood

Release date: January 16, 2011 [eBook #34984]
Most recently updated: January 7, 2021

Language: English

Credits: Produced by Larry B. Harrison and the Online Distributed
Proofreading Team at https://www.pgdp.net

*** START OF THE PROJECT GUTENBERG EBOOK A GUIDE FOR THE STUDY OF ANIMALS ***

Transcriber's note

Obvious punctuation errors have been repaired silently. Word errors have been corrected and a list of corrections can be found after the book.

Table of Contents

A Guide
for the
Study of Animals

By a Committee from the
Biology Round Table of the Chicago
High Schools

  • Worrallo Whitney, Chairman
    Bowen High School
  • Frederic C. Lucas
    Englewood High School
  • Harold B. Shinn
    Schurz High School
  • Mabel E. Smallwood
    Lane Technical High School

D. C. Heath & Co., Publishers
Boston — New York — Chicago


Copyright, 1911,
By D. C. Heath & Co.

1 E 3


PREFACE

The following guide to the study of animals is intended for pupils in secondary schools. It was prepared by the authors at the request of the Biology Round Table, an association composed of the teachers of Biology in the Chicago High Schools, to whom the authors wish to take this opportunity of expressing their appreciation of the many helpful suggestions and criticisms of the manuscript.

The time has passed when a high school course in zoölogy consists simply of a somewhat simplified edition of a similar course in college. All teachers now recognize that the motivization of any course should be its adaptability to the needs of the student, and that zoölogy must be taught from the standpoint of the student rather than that of the subject. In preparing this guide, the authors have tried to keep these points in mind.

The matter of presentation, the order of topics, and the choice of material has been much discussed, but the trend of opinion has finally set in toward an ecological rather than a type study of animals; that there should be in the case of young students a brief study of rather a large number of animals to bring out some general biological law, rather than an exhaustive study of a very few types. It is further recognized that the use of a reference library is absolutely essential in connection with and to supplement the laboratory work, as there are some topics beyond the ability of the young student for original investigation as well as impossible in the amount of time usually allotted to the subject in our crowded curricula. Of great importance is the economic side of zoölogy, especially its bearing upon the applied sciences of medicine, sanitation, household science, and agriculture, and this phase has received special attention in this guide.

The desirability of field work has always been recognized, but the special conditions under which schools must work are so variable as to make any set directions for field work of little value, and so they have in most cases been omitted in this work. Each teacher can easily give such special direction for collecting material and study in the field as the locality of the school and the time available for it shall determine.

Since zoölogy will probably be the pupil's first laboratory science, the authors have preceded the more formal portion of the manual with a series of short exercises on familiar and easily obtained animals in order to introduce the pupil to the laboratory method and to stimulate his interest, training him at the outset to be constantly on the outlook for specimens and to show him how much may be learned from common things right around him, if he will only use his eyes. We have also begun the more formal portion of the guide with insects, since in the fall they are easily collected and may be studied alive. They illustrate, moreover, the principles of classification and method of using keys and other means of finding out the names of animals. This would seem to be pedagogically sound, for some recent experiments with pupils show that the first question that comes into a child's mind upon seeing a new or strange specimen is "What is it?"

A larger portion of the guide is given to the chordates than is usually the case. The authors also believe that this is correct and in accord with the natural interest of the pupil. It will serve to connect his zoölogy more closely with his daily experiences.

There is material enough provided to allow the teacher a chance to select that best adapted to his purposes or conditions as well as to provide for those schools that give more than one year to zoölogy.



CONTENTS

 Page

CHAPTER I

Introductory Studies of Living Animals 1

Fly, 1; Maggot, 3; Cockroach, 4; Spider, 5; Cricket, 6; Grasshopper, 7; Butterfly or Moth, 9; Caterpillar, 10; Tussock Moth, 11; Beetle, 13; Damsel Fly Larva, 14; Plant Lice and Scale Bugs, 15; Water Bugs and Beetles, 17; Getting Acquainted with the Library, 18.

CHAPTER II

Studies of Insects 20

Field Studies, 20; Grasshoppers or Locusts, 23; Comparative Study of Orthoptera, 28; Key to Orthoptera, 29; Dragon Fly, 30; Honeybee, 31; General Study of Insects, 33; Review of Insects, 35; Key to Principal Orders, 36; Some Common Butterflies, 38; Summary of Insects, 37; General Review and Library Exercise, 40.

CHAPTER III

The Connection between Structure and Function 44

Protozoa: A Study of the Cell, 44; Comparative Study, 48; Review and Library Exercise, 49; Sponges, 51; Review and Library Exercise, 53. Cœlenterates: Hydra, 54; Comparative Study, 58; Review and Library Exercise, 59. Worms: Living Earthworm, 61; External Morphology, 64; Internal Morphology, 64; Microscopic Anatomy, 66; Summary, 68; Review and Library Exercise, 70; Connection between Structure and Function, 72.

CHAPTER IV

Adaptation to Surroundings 73

Crayfishes: Living Crayfish, 73; Morphology, 75; Summary, 79; Review and Library Exercise, 81.

CHAPTER V

Adaptation for Protection from Enemies 83

Mollusca: Clam, 83; Snail, 87; Squid, 89; Comparative Study, 91; Review and Library Exercise, 92. Comparative Study of Exoskeletons, 93; Protective Coloration, 94; Animal Associations, 96; Protective Habits and Powers, 98; Defensive Structures, 99; Thesis: "Adaptation for Protection," 99.

CHAPTER VI

Vertebrates 101

Fishes: Living Fish, 101; External Structure, 103; Mouth and Gills, 105; Alimentary Canal and Circulatory System, 107; Review and Library Exercise, 110. Primitive Chordates, 112. Amphibia: Living Frog or Toad, 114; Mouth, 116; Organs of Digestion, Absorption, and Excretion, 117; Organs of Circulation and Respiration, 120; Nervous System, 123; Endoskeleton, 125; Comparative Study, 129; General Review and Library Exercise, 129. Reptiles: Living Snake, Lizard, and Turtle, 130; Review and Library Exercise, 132. Birds: Living Pigeon, 133; Plumage, 136; Birds and Migration, 139; Laboratory Exercise, 139; Field Work, 141; Review and Library Exercise, 142; Migration in General, 145. Mammals: Rodents: Domestic Rabbit, 146; Wild Rabbit, 148; Guinea Pig or White Rat, 149; Squirrel, 150; Library Exercise, 152. Carnivora: Laboratory Exercise, 153; Library Exercise, 155. Ungulates: Laboratory Exercise, 157; Library Exercise, 160. The Horse, 162. Homology of the Vertebrate Skeleton, 168.

CHAPTER VII

Adaptations for the Preservation of the Species 170

Methods of Reproduction: Simple or Asexual Method, 170; Complex or Sexual Method, 171. Development: Structure of an Egg, 172; Development of an Egg, 173; Metamorphosis of a Mosquito, 174; Metamorphosis of a Butterfly, 176; Development of the Chick, 177. Protection and Care of Young: Library Exercise, 179. Adaptation for the Preservation of the Species: Review and Library Exercise, 180.

CHAPTER VIII

Poultry 182


Glossary 189


A Guide for the Study of Animals


CHAPTER I
INTRODUCTORY STUDIES OF LIVING ANIMALS

In the following brief exercises the primary purpose is to arouse an active, attentive interest on the part of the pupil in various forms of animal life which may be at hand, reminding him of what and how various creatures eat, how they breathe, how they get ideas of the world, how they get about, and perhaps how they succeed where others fail. Of secondary importance is the introduction of laboratory methods by easy stages. The pupil should feel that his natural curiosity is only being directed to definite ends and that he is free to investigate in his own way.

The types here given are only a few of the many to be found in the early fall, and these exercises in several cases may be used for other forms than those definitely mentioned. There should be a great deal of promiscuous collecting by the class, and in the mass of material gathered the following types will probably be fairly abundant.

THE LIVING FLY

Materials.

Living flies in cages and individual specimens in small wide-mouth vials with cotton stoppers for the admission of air. Sugar crystals may be used for feeding. Simple lenses.

Observations.

Notice the division of the body into three regions: head, thorax, and abdomen. The six legs, the large wings, and the small feelers may be easily found, as are the large eyes, the extensible mouth, and beneath the larger wings the small undeveloped ones looking like tiny knobs.

  1. State the general color of your specimen and give any special markings on its body.
  2. Is the body smooth or has it a covering of any kind? Do you regard the fly as a cleanly animal? Why?
  3. Under what conditions does the fly use its legs? its wings? What enables it to walk upside down? What use can you assign to the small wings?
  4. Judging by the relative size of the feelers and the eyes, do you think the fly relies more upon its sight or its feeling? Since the eyes can probably see you any place where you see them, determine through how much of a circle the fly can see.
  5. How does the fly eat? Does it eat solid or liquid food?
  6. Where is the extensible mouth (proboscis) kept when not in use? What is the fly doing when "washing its face"?
  7. From your own observation in the barn and the alley what do you know about the fly's cleanliness in choosing its food? How would it affect articles in the pantry?
  8. From the foregoing statements show how flies may be a serious factor in dealing with disease.
  9. What means may be employed as protection against adult flies? against their breeding places and "maggots"?
Suggested drawing.
  1. The entire fly, seen from above, × 4.

THE LIVING MAGGOT

Materials.

Living specimens in pans or cotton-stoppered bottles, with some food material and moist cloth or paper; lenses.

Observations.

Notice the general worm-like form of the maggot, or grub, the plain and uniform color, and the absence of all elaborate structures, as wings and feelers.

  1. Since this creature is destined to become a flying or walking insect, what organs will have to appear? Is there any indication of these structures at present?
  2. Give the color of the specimen, and explain how the presence or absence of strong light seems to have affected the color. Is this effect usual in animals or plants that you know?
  3. Tell how the animal gets from place to place, describing any special structures you find which aid in this work.
  4. How can you tell the head end? Tell how the amount of work that the mouth and mouth parts do affects their size and indirectly that of the region where they are.
  5. What senses and sense organs has the maggot? Test any of these senses or organs gently, by any means at your disposal, or recall any experience you have had along this line. Which senses or organs seem to be best developed?
  6. Explain briefly how the active or sluggish habits either determine or are determined by the condition of the senses or sense organs.
  7. Since "Mother Nature" seems to want maggots to develop rapidly, tell how she economizes in energy and material when forming them.
  8. Show how the development of maggots in refuse matter is actually beneficial.
  9. From the standpoint of flies and human welfare, show why maggots should not be allowed to live,—stating how they may be prevented.
  10. Look up the story of the pupa of the house fly; the development and work of the botfly; of the ox-warble; of the tsetse fly.
Suggested drawing.
  1. The maggot or grub, side view, × 4.

THE LIVING COCKROACH

Materials.

Individual specimens in cages, jars, or wide-mouth vials with cotton stoppers to admit air. Several roaches in large cages with material for food and concealment.

Observations.
  1. What is the general color and the average size of cockroaches?
  2. During what time of the day are roaches most active? Where do they hide at other times? How do their shape and color aid concealment? Note any odd or striking colors or marks which might make them distinguishable to their mates.
  3. Is the roach a quick or a slow moving animal? How does it get about,—by running, jumping, walking, crawling, swimming, or flying? Turn your specimen on its back and see how it recovers its proper position. Notice the relative size and development of the wings and their use in flying.
  4. If uninjured, your specimen has six legs. Why don't they step on each other? Notice the stiff hairs on the legs and the white pads under the feet. How would these structures be useful to the animal?
  5. The large, black, shiny eyes are on the front and sides of the head; the long "horns," or feelers, are attached just below the eyes. Upon which sense, sight or feeling, do you think the roach depends more? Explain your statement.
  6. Beside the mouth are a long and a short pair of "feelers"; perhaps these are for tasting or smelling. What do roaches like to eat? Do they choose their food? What damage do they do?
  7. How can a house be rid of cockroaches?
Suggested drawing.
  1. a. A cockroach, seen from above.

THE LIVING SPIDER

Materials.

Living spiders, preferably large ones, in cages; individual specimens in battery jars or wide-mouth bottles. Cocoons. Simple lenses.

Observations.

Each pupil may feel sure that if treated fairly any of the common spiders may be handled without fear of bite or injury.

  1. Note that the spider's body is of two regions, the head-thorax and the abdomen, and that it is supported by eight legs. To what part of the body are the legs attached?
  2. Find the feelers; if they are club-shaped, your specimen is a male. State their number and tell where they are attached. What is the sex of your spider?
  3. Usually there are eight tiny near-sighted eyes on the front of the head. State the color of the eyes and by a diagram indicate their arrangement.
  4. With what kind of material is the body covered (use the lens)?
  5. What is the color of your specimen? What special markings has it?
  6. Holding the spider aloft in your fingers, allow it to drop upon the thread it will spin, and watch it climb and spin. Record the number of the spinners, their situation, and how they act. Are the threads sticky? If so, why doesn't the spider stick to its web? Is the web used for a home or for a snare?
  7. Try to discover how the feet are enabled to cling to the thread.
  8. Examine a cocoon, noting its outer form and structure, and look for an opening at the top. If you can open a cocoon carefully with scissors, look for its two coats and inspect its contents.
  9. State three uses for the spider's silk.
  10. What is the work of spiders amongst the animal population of the earth, or of what use are they?
  11. Out of doors find webs of various kinds: wheel web, tent web, triangle web, etc.
  12. How do the jumping spiders differ from others in their spinning and feeding habits?
  13. Look up what is meant by ballooning spiders. Find out when ballooning occurs and what is accomplished by it.

Find out the name of your kind of spider.

Suggested drawings.
  1. The entire spider, seen from above.
  2. A cocoon.

THE LIVING CRICKET

Materials.

Living crickets in cages, with materials for food and concealment, and individual specimens in wide-mouth bottles or vials with cotton stoppers.

Observations.
  1. What is the average size and the general color of crickets?
  2. Just what do they do when you try to catch them? What structures enable them to do these things?
  3. Of the three pairs of legs, which extend sidewise for running or grasping, and which backward for jumping or climbing? What structures have the legs to enable them to do their work properly?
  4. Notice how well developed the cricket's wings are, and state how much they are used or how they influence the habits of the animal.
  5. How many projecting spines are there on the hinder end of the body? Are they ornamental or useful? how? The female crickets have a special spear-shaped spine for depositing eggs.
  6. In a column make a list of the senses (sight, feeling, etc.), and opposite each state what kind of an organ is used and where it is located. The ears are oblong white spots on the second long piece of the front legs.
  7. Find out whether the cricket chews solid food or sucks liquid food, and whether it has biting jaws or protrusible lips. See whether it will attack a toothpick or your finger, and if the crickets have been confined long, whether there has been any attempt at cannabalism. Is its natural food animal or vegetable matter?
  8. How do crickets chirp?
  9. What work do they do in nature?
  10. How does a baby cricket develop?

THE LIVING GRASSHOPPER OR LOCUST

Materials.

Individual specimens in wide-mouth bottles or jars, and other specimens in cages, with turf or foliage for food and concealment. Simple lenses.

Observations.

Notice the form and size of your specimen, its color, the number of its legs and of its feelers. Find the eyes; the two large eyes, a tiny one between the two feelers, and near the inner edge of each large eye, another tiny one. With a lens notice the markings on the large eyes. Find the mouth, and note its lips and finger-like feelers. Draw out an outer wing, and then carefully draw out the delicate under wing, allowing them both to fold into place again. Under the wings find the circular or crescent-shaped membranes, the eardrums. Watch the grasshopper's body expand and contract in breathing, and find the small breathing holes along each side the body. Compare its rate of breathing with your own.

Questions.
  1. In what surroundings and how does the grasshopper's color protect it? What color markings has it which might serve for other grasshoppers to see as signals? Explain how this signaling is done.
  2. Explain how the legs are placed so as to act as springs in jumping and alighting.
  3. What advantages in having the wings attached on the upper side and the legs on the under side of the body?
  4. Explain how the small wings are protective, and how the large ones are protected.
  5. Why is it better for the grasshopper to have its mouth on the under side of its head instead of in front?
  6. The large eyes are supposed to be far-sighted, the small ones near-sighted. State how the large eyes have the more advantageous position, and around how much of a circle they can see.
  7. Describe how the grasshopper breathes.

THE LIVING BUTTERFLY OR MOTH

Materials.

Individual specimens in large jars or cages, and other specimens in cages with foliage; simple lenses and a needle or pin.

Observations.

Butterflies may generally be distinguished from moths by their habit of holding their wings together above them when at rest, by the feelers which are knobbed at the end, and by the rather slender abdomen. Moths generally either fold their wings or hold them outstretched, their feelers are not knobbed, and their bodies are rather bulky.

Observe these points in your specimen and the colors of the upper and under sides of the wings. Find the large eyes and examine them with a lens. With the needle or pin carefully uncoil the sucking tube which you may find under the head between two shields. Note the fuzziness of the body and the "dust" which covers the wings. Examine some of this dust under a lens.

Questions.
  1. Is your specimen a butterfly or a moth? Prove your statement. If possible, give the name of your specimen.
  2. Write a description of your specimen—its size, general color, and special color pattern.
  3. Describe the sucking tube, or "proboscis," and name some flowers from which it might obtain nectar. Try to find out how the tube is operated.
  4. Why is it that moths and butterflies never bite? Do they sting? How do you think they protect themselves from enemies?
  5. State how the fuzz and dust on your specimen might influence a bird's liking for it.
  6. Contrast the size and usefulness of the wings of the butterfly with those of some other insect you know about; contrast their legs; state how development of one set of structures may cause another set to be simple or feeble.
  7. Most moths are active by night. What explanation can you give for their large eyes and expanded feelers? Feelers of insects may be for any or all of the following: touch, taste, smell, and hearing.
Suggested drawings.
  1. The butterfly or moth.
  2. An antenna (feeler).

THE LIVING CATERPILLAR

Materials.

Living caterpillars in cages or covered jars for individual study, and other specimens in cages with foliage for food or concealment.

Observations.

The pupil should observe the general form and external construction of the caterpillar, watching it feeding, in action, and at rest.

Notice how the creature moves. Find its head, its segments (similar divisions of the body), and its breathing holes along the sides of the body. Try to find its eyes, any feelers, wings or paddles. Try to loosen it from its support; find the tiny hooks on the feet for clinging fast.

Questions.
  1. Give the general color of your specimen and explain how this color may make it conspicuous or may aid its concealment.
  2. Describe the outer surface or covering of the caterpillar. What structures, if any, are there, which might make the animal distasteful or inedible?
  3. How many pairs of legs are there? How are they distributed along the body? Counting the segments, state which ones bear no legs.
  4. To what extent do the legs act in locomotion? Are they mere organs for attachment while the body swings forward and backward, or do the legs do this, as in a horse? Make a complete statement.
  5. Notice the openings of the internal breathing tubes. How are they protected against dust and other foreign matter?
  6. Does the caterpillar seem to be a warm-blooded animal? State how the free access of air along the body would influence internal temperature.
  7. What do you know about a caterpillar's appetite? How might caterpillars be beneficial or harmful? What means has nature of holding their numbers in check?
  8. Recalling that caterpillars finally "sleep" for several days or weeks and awaken as winged creatures, how can you account for their appetites?

THE TUSSOCK MOTH

Materials.

Directions for the study of the caterpillar stage will be found in the exercise "The Living Caterpillar," and directions for the study of the adult male form will be found in the exercise "The Living Butterfly or Moth." The female tussock moth is a wingless, thick-bodied creature, gray in color, very downy, and about three fourths of an inch long. The following directions apply more particularly to the study of the cocoons and the general harmfulness of the tussock moth.

This exercise may be done best outside of the classroom, the pupil answering the questions on scrap paper and rewriting these notes in the laboratory. Living caterpillars, cocoons, some of them bearing their frothy masses of wax and eggs, pupæ, and adult moths of both sexes may be used in the laboratory.

Observations and Questions.
  1. On what kinds of trees are the cocoons and the caterpillars generally found? What effect have the caterpillars on the trees, and what may possibly be the final effect upon the trees of the locality or the entire district?
  2. Upon what part of the tree are the cocoons made, and why? Where on the bark are they, and why?
  3. Is the opening of the cocoon at the upper or the lower end? What reason can you assign for this?
  4. Count the number of cocoons upon the entire tree or estimate it by counting those upon a part of the tree. Now count the number of eggs on a cocoon. Assuming that one half of the cocoons bear eggs, calculate the number of caterpillars on a tree next year.
  5. How is the waxy covering of the eggs a particularly good protection against winter weather?
  6. Investigate the interiors of several cocoons and state what you find.
  7. On the pupa find the jointed and tapering hinder end, abdomen, and at the head region and lying along the under side, the marks of the legs and the feelers, and possibly the wings, all pressed close against the body. Find also the breathing pores along the sides of the abdomen.
  8. Unlikeness between male and female is called "sexual dimorphism." Explain how the tussock moth shows this. For what work does each form seem particularly adapted?
  9. What methods would you use that the tussock moth might be destroyed or kept out of a community?

The numerous small worm-like creatures often found are the caterpillar stages of another insect, an ichneumon fly, which laid its eggs under the skin of the tussock caterpillar. How has their development affected that of the tussock moth? What great result does nature accomplish by this arrangement?

Suggested drawings.
  1. A caterpillar, × 2.
  2. A cocoon with its egg mass.
  3. A pupa as seen from the under side.
  4. An adult moth, either male or female.

THE LIVING BEETLE

Materials.

Living beetles in cages, together with portions of the plant upon which they are found; or if water beetles are used, they should be kept in aquaria. Individual specimens in battery jars or wide-mouth bottles, and preserved beetles in pans or vials for reference.

Observations.
  1. Upon what plant or in what surroundings is your kind of beetle generally found? If you can, give its common name.
  2. What is the length, breadth, and thickness of your beetle? Would you describe it as a "small" insect or a "large" one?
  3. Of what general color is it? Describe any color markings you see.
  4. If any of the legs differ from the others or are of peculiar shape or length, describe them and tell what you think they may be fitted to do.
  5. As a rule, beetles have harder "shells" than other insects. Does this shell completely inclose the body, or can you find any soft parts exposed? How are the head, thorax, and abdomen joined so as to carry out the apparent purpose of protection? What is the outline of the body—a continuous line or one with many irregularities?
  6. If possible, try to lift up one side of the "shell" from the hinder end of the body. You will discover that this portion of the shell is a pair of hard sheath wings, and beneath them is another pair. How are the under ones unlike the upper in size and texture? in use? in arrangement when not in use?
  7. Does a beetle spend most of its life on the wing, like bees and flies? How might the body covering and the structure of the outer wings affect or determine the beetle's habits, even against its will?
  8. Are the feelers or are the eyes of your specimen more easily distinguished? Upon which of the special senses does it seem to place most dependence?
  9. Is your kind of beetle good for anything, either in nature or in human affairs? Make a statement regarding what good or what harm it may do.

THE DAMSEL FLY LARVA

Materials.

Living larvæ of the damsel fly in shallow watch glasses of water for individual use, and others in large pans or aquaria. Simple lenses or dissecting microscopes.

Observations.
  1. What is the color and the shape of the larva? how long is it? Notice in what surroundings in the water the larva lives, and answer to yourself how its form and color would protect it in those surroundings.
  2. Since the larva is an insect, though immature, its body is composed of three regions: head, thorax, and abdomen. How do these regions differ from each other?
  3. What structures has your specimen to enable it to move from place to place? If fully developed wings are not present, what indication is there of their being formed?
  4. What sense organs has the larva? Which ones seem to be the largest and most useful?
  5. Although the aquatic larva is preparing for adult life in the air, there should be some arrangement for securing air in the water. Where do you find outgrowths of the skin which might increase the air-absorbing surface? How many of these structures are there? Look within them for the air tubes,—fine branching black lines.
  6. If possible, without injury to the specimen, examine the larva's mouth. Try to discover how it is used and how it is protected when not in use.
Suggested drawings.
  1. The entire larva, × 4.
  2. A gill, as seen through the microscope.
  3. The feeding apparatus, × 10.

PLANT LICE AND SCALE BUGS

Plant Lice (Aphids)
Materials.

Plant lice on various kinds of plants, such as house plants, golden glow, and other plants from the garden or field. Garden asters with root lice (the asters should be transplanted into pots).

Observations.
  1. Describe the size, appearance, and colors of the plant lice in your collection and their relation to the host plant.
  2. Are the lice active or sluggish? (Compare with a house fly, for instance.) What proportion of them have wings? What is the usual method of locomotion?
  3. Examining a single winged specimen, how many wings do you find? How do they fold? What is the character of the wings?
  4. What is the food of the plant lice? How is the food obtained? (With a hand lens identify the piercing organ.) On what parts of the plants are they found? Does the plant show any indication of being harmed by the lice? If so, how?
  5. Make a count of the plant lice upon a portion of a plant and estimate the whole number upon a plant. Why are plant lice a very serious pest?
  6. If any plant lice have ants associated with them, study the behavior of the ants in this curious relationship. What advantages result from this relationship of ant and aphis to either or both insects?
Scale Bugs
Materials.

Twigs of trees, leaves, fruit, ferns, etc., infested with these bugs. If possible, have samples of San José scales, maple scales, and oyster scales.

Observations.
  1. What is the general size and appearance of the various scale bugs in your collection? How do they differ in form and size and color?
  2. Remove a scale and study it carefully with a lens. What is under the scale? Of what is the scale composed? What do you discover about these bugs to indicate that they are really insects?
  3. What can be said about the number of scale bugs? Why are they difficult to exterminate? How can they be distributed from one place to another, as from orchard to orchard, since only the males have wings?
Drawings suggested.
  1. A single aphis as seen with hand lens.
  2. Various scale bugs as seen with a hand lens.
  3. Twigs showing the distribution and numbers of scale bugs.

WATER BUGS AND BEETLES

Water Bugs
Materials.

Water bugs and beetles of several species in small aquaria covered with a wire net.

Observations.
  1. With what legs does the bug swim? Describe their appearance and tell how used and how fitted for this use. Which legs are not used in swimming?
  2. Remove the bug from the water for a moment to test other methods of locomotion, as jumping, crawling, flying. What do you discover?
  3. Watch the bug as it gets a fresh supply of air, and describe the process. Where is the air stored for use when under water? Does the bug sink or rise when it stops swimming? Why?
  4. Identify the bug's mouth parts. What is their appearance and probable manner of use? How are the forelegs fitted for grasping food?
  5. What is the shape of the body? What is the position of the wings? Do the two cover (fore) wings meet in a straight line or do they cross at their tips? Are they smooth throughout and sheath-like, or are they thick at the base and thin at the tips?
Summary.

Summarize your study of the bug by enumerating the various ways the bug is adapted for life in the water.

Water Beetles

Use the same questions for the study of water beetles as for water bugs. In addition answer the following:—

  1. Identify the eyes of the whirligig beetle and note their peculiar construction. How can you explain this peculiar form of the eyes on the basis of use? Why are the antennæ of both water bugs and beetles so small?
Suggested drawings.
  1. The dorsal view of both bug and beetle.
  2. Ventral view of the bug's head to show the beak and first pair of legs.

GETTING ACQUAINTED WITH THE LIBRARY

Directions.

The books in a zoölogical library may be roughly divided into three groups:—

  1. Reference books.
    1. Advanced textbooks.
    2. Elementary textbooks.
    3. Natural histories.
    4. Books for classifying or naming animals.
  2. Descriptive books.
    1. Life histories and habits of animals.
    2. Adventures with animals—popular accounts of animals seen on walks and travels.
  3. Economic zoölogy.
    1. Books on harmful animals and methods of destroying them.
    2. Books on useful nondomesticated animals and their products.
    3. Books on domestic animals.
    4. Books of a general nature not included in the above.

Examine as many of the books in your library as you can and record for each one in your notebook:—

  1. Title of the book; author's name; publisher; date of publication.
  2. The kind of book as classified above.
  3. What it includes or what animals or topics are covered by the book.
  4. Whether the style is popular or technical, i.e. whether it is easy for you to read.
  5. The general character of its illustrations and whether they appear to be especially helpful.
  6. Comments on the value or interest of the book as it appears to you.
  7. Select a book which interests you, for future reading.

CHAPTER II
STUDIES OF INSECTS

The effect of great numbers upon the structure and habits of animals. The use of keys in finding the names of animals.

1. FIELD STUDIES

Materials.

1. Boxes for carrying insects. 2. A net. This may be homemade, using mosquito netting or fish net and a stout wire. If it is to be used for a dragnet for water insects, the wire must be stout and the netting strong. Make the net twice as long as wide. 3. A cyanide jar for killing insects. 4. A few paper triangles for carrying butterflies. 5. A notebook.

Note.—Your instructor will give directions for obtaining the material called for in 3, 4, and 5.

Directions.

Look carefully and quietly in the various situations noted below. Do not be in a hurry. Weedy meadows or vacant lots and neglected roadsides are good places for your first trips. Note concerning each insect found: (a) its name or something by which to identify it, (b) where you found it, (c) what it was doing, (d) its probable food. Record these observations in your notebook. Make a special study of such insects as your instructor may designate.

Where to look for Various Insects
Grasshoppers, locusts, katydids.
Look along roadsides, waste places, gardens, especially weedy ones, weedy lots, and grassy meadows and pastures.
Crickets.
Under old boards, along the edges of board or stone walks, along fences.
Beetles.
Same locations as for crickets, and also on flowering plants, under loose bark of trees and stumps, in rotten logs, etc. For water beetles drag edges of ponds and streams.
Dragon flies.
Along water-courses, ponds, and swamps. Drag ponds and ditches for larvæ.
Bees.
On flowering plants, especially on large patches of wild asters, golden-rods, and thistles.
Wasps.
Sandy stretches,—especially along the water,—among flowering plants, under the eaves and roofs of outbuildings. Nests may be found in these latter places.
Butterflies and moths.
In fields where there are many flowering plants; look carefully on the leaves of plants for caterpillars, and for eggs. Also look very carefully on the under side of leaves, on twigs, and on the bark of trees for chrysalids of butterflies and cocoons of moths.
Bugs.
In same locations as for bees and grasshoppers and water beetles. Also on fruit.
Aphids.
On the fresh growing tops of plants.
Tree hoppers.
On trees and shrubs. Hold your net on the under side of branches and shake the branch vigorously.
Flies.
Around decaying substances, as garbage, fruit, etc.; on flowering plants.
Ants.
Sandy waste places, decayed logs, along walks, often in kitchens.

Note.—At night many kinds of insects fly around electric lights or into open windows, attracted by the light and may easily be collected.

Form for Field Trip Report

The notes taken on a field trip may be conveniently tabulated for permanent record in the form indicated below:—