TABLE OF CONTENTS. 



Introductory Note and Acknowledgments, by Dr. Charles C. Adams. 



PART I. ECOLOGICAL PAPERS. 



1. Isle Royale as a Biotic Environment, by Dr. Charles C. Adams 1 



I. Introduction 1 



1. Itinerary and Personnel of ther Party 1 



2. Aims and Method of Work 2 



3. Previous Biological Investigations upon Isle Royale 4 



4. Historical Note.. , 5 



5. Available Maps of Isle Royale 5 



II. The Biota Considered by Stations 6 



1. Location of Field Stations in 1905 6 



2. General Characteristics of the Stations 8 



III. The Evolution of the Gross Environment 31 



* 1 . Geological Succession 31 



2. Topography and its Origin 39 



3. Atmospheric Influences and their Evolution - 41 



a. Chmate 41 



b. Seiches 44 



c. Climatic Succession 45' 



d. Lake Storms and their Influence 46 



4. Surface Currents of Lake Superior 47 



5. Origin of the Habitats 50 



2. The Ecological Relations of the Invertebrate Fauna of Isle Royale, Michigan, 



by Dr. H. A. Gleason 57 



I. Introduction 57 



II. The Lake 58 



III. The Inland Lakes 63 



IV. The Tamarack Swamp and the Arbor Vitae Swamps 6,5 



V. The Gravel and Sand Beaches 66 



VI. The Rock Beach .• 69 



VII. The Cladonia Clearings and Jack Pine Ridges 71 



VIII. The Balsam-Spruce Forest : 75 



IX. Artificial Clearings 77 



X. Summary 77 



3. The Ecological Distribution of the Birds of Isle Royale, Lake Superior, by 



Otto McCreary 81 



I. Introduction 81 



II. Light-house Peninsula, (between Rock Harbor and the Head of Conglom- 

 erate Bay) 81 



1. Lake Superior and Beach (Station I, Sub. 1.) 81 



2. Spruce and Balsam Forest (Station I, Sub. 2 and 3) 82 



3. Tamarack and Arbor Vitae Swamps (Station I, Sub. 4) 84 



4. Jack Pine Ridge (Station I, Sub. 5) 84 



5. Sphagnum and Spruce Bog (Station I, Sub. 6) 85 



6. Valley at the Head of Conglomerate Bay (Station I, Sub. 1) 85 



III. Trail to McCargoe Sove 85 



1. Ransom Clearing (Station II, Sub. 1) 85 



2. Benson Brook (Station II, Sub. 1) 86 



3. Spruce and Tamarack Swamps (Station II, Sub. 2 and 5) 87 



4. Rock Ridge Clearings (Station II, Sub. 3) 87 



