PREFACE 



With the ever-expanding demands of various curricula, the in- 

 structor in charge of a beginning zoology course faces a dilemma. At 

 the same period that the time allotted for general zoology is being re- 

 duced or at least not expanded, new and basic discoveries must be in- 

 corporated. No longer is it sufficient merely to march through the ani- 

 mal kingdom, studying a few types here and there along the way. Re- 

 cent discoveries in physiology, such as the Rh factor in blood, the theory 

 of nerve conduction, the dynamic state of bones, and many others 

 must be correlated with the basic anatomy of the systems involved. 

 Genetics discussions must be expanded to include new discoveries in 

 cytoplasmic inheritance and biochemical genetics. A survey of the 

 animal kingdom must unite the various phyla into a phylogenetic scheme 

 which makes sense to the student and yet gives him a clear picture of 

 representative forms. Even here new material must be incorporated. 

 With increasing world travel, many tropical parasites, formerly of little 

 significance to the elementary student, now are topics of popular dis- 

 cussion. 



It also appears to us that in addition to providing our students with 

 the necessary technical background, we have failed if we have not 

 given them an esthetic appreciation of the world of life. It would seem 

 as important for them to appreciate the beauty of the biological world 

 as that of a symphony or a Shakespearian play. All seem to be equally 

 part of the added enjoyment of life that should come from a college 

 experience. 



Here at Purdue, we have been faced with the same dilemma. We 

 feel that it is impossible to cut whole areas from the course to find 

 room for the new ideas and concepts. Mere adding to, piling new 

 facts on old, would only increase our problem of size. What we have 

 been forced to do is to re-examine all the basic materials and then 

 save space and time for new concepts not necessarily by deletion but 

 by careful integration. In so doing, we have developed a course which 

 we believe provides the necessary technical background for our stu- 

 dents in the curricula in general agriculture, preveterinary, predental, 

 premed, prepharmacy, medical technician, and zoology, as well as the 

 humanistic appeal that should be an integral part of biology. 



In this course, after a brief introduction to the study of science, 

 scientific method, protoplasm, classification, and other background ma- 



