INTRODUCTION 



13 



from the research on them. Without ani- 

 mal experimentation there might be no 

 protection against rabies, smallpox, diph- 

 theria, typhoid and undulant fevers, and 

 many other diseases which plague the ani- 

 mal world. The value of lower animals in 

 scientific work generally cannot be overem- 

 phasized. 



Food and animal products 



Animals are very useful to man because 

 of their value as food. Almost every phylum 

 or class of the larger animals contains at 

 least a few species that reach our tables. 

 These include especially the shellfish, lob- 

 sters, crabs, shrimps, fish, turtles, frogs, 

 birds, and mammals. We depend largely, of 

 course, on domesticated birds and mammals 

 for our supply of meat. Animal products are 

 hardly less important; among these are 

 sponges, corals, pearls and pearl buttons, 

 honey, beeswax, silk, tortoise shell, feathers, 

 fur, and leather. 



Harnifid animals 



Destructive animals fall principally into 

 two types, predaceous animals and parasites. 

 We need not fear direct attacks of predatory 

 animals, but many useful wild and domestic 

 animals are killed by them. Parasites not 

 only destroy or make unhealthy large num- 

 bers of useful wild and domestic animals, 

 but also attack man, and every year bring 

 sickness or death to millions of human be- 

 ings. These parasites are mostly protozoans, 

 flatworms, roundworms, and insects. The 

 insects, mites, and ticks not only attack man 



directly, but many also carry disease germs 

 from nonhuman animals to man, from man 

 to man, or from animal to animal. A few 

 animals, including certain insects, spiders, 

 scorpions, fishes, and snakes, are poisonous 

 to man. More details regarding the relations 

 of the various types of animals to man are 

 presented in the chapters which follow, 



SELECTED COLLATERAL 

 READINGS 



The books listed here and in other chapters 

 comprise a few selected works and are intended 

 only as suggestions to the beginning student. 

 Many of the texts cited have extensi\e bibliog- 

 raphies which give a ready entrance into the 

 zoological literature. The following works in- 

 clude taxonomic reviews of the animal king- 

 dom: 



Caiman, W.T. The Classification of Animals: 

 An Introduction to Zoological Taxonomy. 

 Methuen, London, 1949. 



Hyman, L.H. The Invertebrates: Protozoa 

 Through Ctenophora. McGraw-Hill, New 

 York. 1940. 



Manville, R.H. "The Principles of Taxonomy." 

 Turtox News, 30: No. 1 and No. 2, 19 52^ 



Mayr, E., Linsley, E.G., and Usinger, R.L. 

 Methods and Principles of Systematic Zool- 

 ogy. McGraw-Hill, New York, 1953. 



Schenk, E.T., and McMasters, J.H. Procedure 

 in Taxonomy. Stanford Univ. Press, Stan- 

 ford, 1956. 



Simpson, G.G. The Principles of Classification 

 and a Classification of Mammals. Bull. Am. 

 Mus. Nat. Hist., Vol. 85, New York, 1945. 



