CONTENTS. 



Department Bxjxletin No. 433. — Changes in Fresh Beef During Colb Page. 

 Storage above Freezing. 



Hygienic value of cold stoi'age 1 



Commercial practices in the cold storage of fresh beef 2 



Previous investigations on cold storage of meats 5 



Purpose and plan of present investigation 7 



Autolysis exi^eriments 8 



Cold-storage experiments with fresh beef 29 



Effects of cold storage upon the nutritive value of the beef 95 



Factors affecting the time that fresh beef can he stored at tempera- 

 tures above freezing 1 97 



General summary 99 



Department Bitxetin No. 484. — Judging the Dairy Cow as a Sitb.ject 

 OF Instruction in Secondary Schools. 



Classroom discussion 1 



Practice judging 16 



DEPARTilENT BUXLETIN Xo. 435. ThE ApPLE LeAF-SEWER. 



History , 2 



Distribution 2 



Feeding habits and character of injury 2 



Description of stages 4 



Spring pupation of A^intering larvae 6 



Emergence of moths ! 7 



Oviposition of moths 8 



Length of life of moths 8 



Habits bf moths 9 



Incubation of eggs 9 



Larval feeding period 10 



Hibernation 10 



Natural enemies 11 



Remedial measures : 11 



Summary 12 



Department Bulletin No. 436. — The Desert Corn Flea-beetle. 



Introduction l 1 



Distribution 2 



Economic considerations 2 



Food plants 4 



Descriptions 5 



Life history and habits ^ 7 



Seasonal history 15 



Natural enemies 16 



Remt'dial and preventive measures 18 



Sunmiary 21 



Department Bulletin No. 437. — Flat-headed Borers Affecting Forest 

 Trees in the United States. 



Importance of flat-headed borers 1 



Food plants 2 



Character of the work 2 



Life liistory , 2 



SeasoMMJ liistory 2 



Spfcial li!d)its^ 3 



Spcfiai structural characters 3 



.\gre<'iiiciil of a(hilt and larval clas.sificatlons .4 



f )istiiigiiiHhing fliarac-tors__ 4 



Key to genera of bui)r<'Slid larv.-r 5 



List of genera, distrilmiion, connnon habits, and host trees 6 



References to Important lilcrafure 8 



