6 DEPARTMENT OF AGRICULTURE BULS. 626-650. 



Page. 

 Department Bulletin No. 640. — The Mediterranean Fruit Fly: 



Distribution throughout the world 2 



Establishment and spread in Hawaii 3 



How the fruit fly got into Hawaii 4 



Losses incurred through the fruit fly 5 



What the Mediterranean fruit fly is like 7 



Fruits, nuts, and vegetables attacked 11 



Host fruits of commercial value 15 



Artificial methods of control not satisfactory under Hawaiian conditions . . ,24 



The campaign against the fruit fly in Hawaii 26 



Natural control of the fruit fly • 37 



Quarantine measures to prevent introduction 41 



Summary 42 



Department Bulletin No. 641. — Farm Practice in the Production of 

 Hay in Steuben County, N. Y., and Washington County, Pa.: 



Object and scope 1 



Facts brought out '. 1 



Description of areas studied 2 



Labor charges for different operations 4 



Machinery charges 12 



Total cost of producing hay 14 



Department Bulletin No. 642. — The Four Essential Factors in the 

 Production of Milk of Low Bacterial Content: 



Factors influencing the sanitary quality of milk 1 



Objects of the investigation 3 



Description of barn and methods used in the production of the milk 3 



Method of sampling and making the bacterial count 5 



The experimental work 5 



Contamination of milk by unsterilized utensils 25 



Contamination of milk by manure and dirt 32 



The three most essential factors in the production of milk of low bacterial 



content 38 



A practical demonstration on six farms 39 



Bacterial counts of fresh milk on the average farm 43 



The effect of temperature on the growth of bacteria in milk 45 



Summary 58 



Conclusions 59 



Literature cited 61 



Department Bulletin No. 643. — The Melon Fly: 



What the melon fly is like 3 



Origin and distribution 4 



Establishment and spread in Hawaii 4 



Methods of spread 7 



Economic importance 7 



Nature of injury caused by the melon fly 8 



Food or host plants 16 



Interesting facts concerning the adult fly 22 



Why the melon fly is a serious pest 24 



Control measures 25 



Measures taken to keep fruit flies of Hawaii from gaining a foothold in 



Continental United States 29 



Summary 30 



Department Bulletin No. 644. — Lint Percentages and Lint Index of 

 Cotton and Methods of Determination: 



Relation of lint percentages to lint indexes 1 



Lint percentages 2 



Lint indexes 2 



Illustrations of the relation between lint percentage and lint index 3 



Lint index determines the number of bolls to the pound of fiber 5 



Relation of the lint index to the cost of picking 5 



