A Guide for the Study of Animals Part 57

4. Describe the nests of five or more of the following: spider, honeybee, b.u.mblebee, paper wasp, mud dauber, digger wasp.

5. Describe the nests of the following: stickleback fish, sunfish.

6. Describe the nests of ten birds common to your neighborhood.

7. Describe the homes of the following: woodchuck, mole, squirrel, rabbit, muskrat, prairie dog, beaver, bear.

8. In case of birds which of the parent birds builds the nest and cares for the little birds?

9. How are the young cared for in the following cases: crayfish, cyclops, pipefish, Surinam toad?

_Summary._

1. What general methods are there for protecting the young?

2. What various devices for a.s.suring plenty of food for the developing animal?

3. What is the relation between the care given the young and the number of eggs produced?

#D. ADAPTATIONS FOR THE PRESERVATION OF THE SPECIES#

Review Questions and Library Exercise

1. Show how the s.e.xual method of reproduction tends to produce variations.

2. What is meant by the term _heredity_?

3. What are chromosomes? What do some zoologists believe to be the relation between these chromosomes and heredity?

4. What are dominant and recessive characters? What is meant by "Mendel law of heredity"?

5. What is meant by the term _parthenogenesis_? What are some of its advantages and under what conditions does it take place? Name some animal in which parthenogenesis commonly takes place.

6. What is s.e.x dimorphism? Give some examples.

7. What were the experiments of Professor Loeb and others in connection with artificially fertilized eggs?

8. How do eggs vary as to the kind of sh.e.l.l, amount of food, size, etc.? What is the effect of the amount of food upon the rate of development? On the stage of development at which the egg is hatched?

9. Contrast praecocial and altricial birds.

10. What is the effect of ground nesting and tree nesting upon the number of eggs and the care of the young?

11. Describe the metamorphosis of gra.s.shopper, June beetle, honeybee, dragon-fly, cicada, may-fly, ant-lion, caddis fly.

12. Compare the development of the crayfish, crab, and lobster. What names are given to the larvae? What is the significance in the fact that the lobster hatches in the "mysis stage"?

13. What are some of the peculiar names given to the larvae in the case of echinoderms, worms, and mollusks? Why should these have received special names?

14. Name the three primitive germ layers. State the princ.i.p.al organs derived from each in the higher animals.

15. What is ontogeny? phylogeny? What is the meaning of the law "The ontogeny is an epitome of the phylogeny"?

16. Who was Weissman? What important contribution did he make to zoology?

17. With what phase of zoology is the name of T. H. Morgan a.s.sociated?

CHAPTER VIII

POULTRY

_Materials._

Either pictures or specimens of the different breeds of fowl.

_General Information._

Under the term poultry are included chickens as well as turkeys, pigeons, ducks, geese, etc. Chickens are most generally raised, since they do not require such special conditions as the others. In this exercise only this form of poultry is considered.

The hen has been domesticated from prehistoric times, being probably derived from the so-called jungle fowl of India (_Gallus bankiva_), which is still to be found in its native habitat. Through constant attempts to improve the domestic fowl along the lines of greater egg-production, size, etc., there have been developed a great many different breeds of fowl. These may be divided into seven groups, as follows:

1. The American Cla.s.s.

2. The Asiatic Cla.s.s.

3. The Mediterranean Cla.s.s.

4. The English Cla.s.s.

5. The Dutch Cla.s.s.

6. The French Cla.s.s.

7. The Ornamental and Exhibition Cla.s.ses.

The American Cla.s.s includes fowls raised both for egg-production and for eating. It includes the following well-known breeds: the Plymouth Rocks, the Wyandottes, the Rhode Island Reds, and the less-known breeds of Javas, Dominiques, and Jersey Blues. These all lay good-sized brown eggs, are good winter layers, and stand confinement well. The standard weight varies from six and one half pounds to seven and one half pounds for the hen, and from eight and one half pounds to nine and one half pounds for the c.o.c.k, the Plymouth Rocks being the heaviest of the breeds.

There are three princ.i.p.al varieties of Plymouth Rocks--the Barred Rocks, with grayish-white plumage regularly crossed with bars of blue-black, the White Rocks, and the Buff Rocks. All have single upright combs, which, with the wattles and the ear lobes, are bright red, a large bright eye, and yellow legs.

There are also three princ.i.p.al varieties of Wyandottes. The Silver-laced Wyandotte has a silvery-white plumage, with black markings in various parts of the body. The Golden Wyandotte is similar in its markings, but has yellow where the Silver-laced has white. The White Wyandotte is pure white. All have rose combs, red ear lobes, and yellow legs. They are on the average about a pound lighter than the Plymouth Rocks.

The Rhode Island Reds are a much more recent breed that has of late become very popular. They are of a reddish-brown color, about the weight of the Wyandotte, with yellow legs. There are both single combed and rose combed varieties.

The Asiatic Cla.s.s includes those breeds raised chiefly for the table.

The Brahmas, Cochins, and Langshans are the chief breeds. They are considerably heavier than other breeds, and are specially characterized by the feathers on the legs and feet. They all lay brown eggs, and are in many cases good layers.