CONTRIBUTIONS FROM THE ZOOLOGICAL LABOBA.TORT OP THE MUSEUM OP COMPARATIVE ZOOLOGY AT 



HARVARD COLLEGE. NO. 248. 



OLFACTORY REACTIONS IN AMPHIBIANS 



JONATHAN RISSER 



ONE FIGURE 



CONTENTS 



Introduction 618 



Food and odors 618 



1. Relation of odors to food 618 



2. Materials and methods 619 



3. Experiments ^ 620 



4. Experiments with non-living food 624 



Food and darkness 625 



1. Materials 625 



2. Experiments 626 



3. Abnormal odors and darkness 627 



Odor-stream experiments 628 



1. Apparatus 628 



2. Rate of flow of odor-stream 630 



3. Methods 630 



4. Substances used in the tests 631 



5. Experiments 631 



6. Controls and operations 634 



Experiments with tadpoles 638 



1. General 638 



2. Methods 639 



3. Experiments 640 



a. First set of tadpoles 640 



b. Second set of tadpoles 611 



c. Third set of tadpoles 641 



Discussion 645 



1. Toads 645 



2. Tadpoles 647 



3. Conclusion 648 



Summary 649 



Bibliography 651 



617 



