6 DEPARTMENT OF AGRICULTURE BULS. 601-625. 



Department Bulletin No. 617. — Australian Saltbush — Continued. page. 



Value for hay 10 



Diseases 10 



Summary 11 



Department Bulletin No. 618. — Experiments with Durum Wheat: 



Introduction 1 



Sources of data 1 



History 3 



Agronomic adaptation and production 5 



Description and key 9 



Varietal experiments 13 



Summary of results 57 



Bibliography 61 



Department Bulletin No. 619. — Food Habits of the Swallows: A Family 

 op Valuable Native Birds: 



Food habits of the swallows 1 



Purple martin 3 



Cliff, or Eaves swallow 6 



Barn swallow 11 



Tree, or White-bellied swallow 15 



Violet-green swallow 19 



Bank swallow 21 



Rough-winged swallow 25 



Tabular summary 28 



Department Bulletin No. 620. — Effect of Varying Certain Cooking 

 Conditions in the Production of Sulphite Pulp from Spruce: 



Purpose of the experiments 1 



Sulphite process 2 



Kinds of wood used 3 



Present methods of operation 4 



Plan of tests 5 



Apparatus 5 



Method of conducting experimen ts 7 



Effect of varying the ratio of free to combined S0 2 , or the amount of lime 



in the cooking liquor 14 



Effect of varying total sulphur dioxide 18 



Effect of varying the temperature of cooking 19 



Summary of results 21 



Methods of analysis and other tests ". 22 



Analysis of cooking liquor 22 



Department Bulletin No. 621. — The Crow and Its Relation to Man: 



Introduction 1 



Systematic position and distribution of the crow 2 



Life history 4 



Information from correspondents 9 



Food habits 10 



Distribution of live-stock diseases 68 



Distribution of seeds 68 



Natmal enemies 71 



Protection of crops 73 



Legislation 80 



Summary 81 



Conclusion 85 



List of items identified in stomach* 86 



Index 91 



Department Bulletin No. 622. — The Identification of Varieties of 

 Barley: 



Varieties of barley 1 



Review of the literature 3 



Variable factors in cultivated barley 5 



Scheme of classification 8 



Lines for further stud y 25 



Identification of thrashed material , . 26 



Varieties grown in field culture in the United States 28 



Key to commercial varieties 28 



Summary 30 



Literature cited 31 



