6 DEPAKTMENT OF AGRICULTURE BULS. 1076-1100. 



Department Bulletin No. 1086. — Shrinkage of Soft Pork Under Com- 

 mercial Conditions: Page. 



Causes of soft and oily pork 2 



Tests on a commercial scale 3 



Plan of experiment 4 



Methods of handling the meat 5 



Results 7 



The true difference in the oily, soft, and firm pork 9 



Prices of the three grades of meat compared 12 



Summary 13 



Appendix — 15 



Department Bulletin Xo. 1087. — ^Alfalfa Root Studies: 



Scope of the study 1 



Factors tending to produce modifications of root growth 2 



Soil conditions 2 



Climatic conditions 3 



Cultural factors 3 



Abnormalities due to injuries 6 



Varieties studied 9 



Conditions under ■n'hich varieties were grown 10 



Difficulties encountered in getting comparable data 11 



Characteristic root systems of some of the well-known varieties of alfalfa. . 12 



Nonhardy alfalfas 13 



Common alfalfas 14 



Turkestan alfalfa 18 



Grimm alfalfa 19 



Yellow-fiowered alfalfa 21 



Summary 24 



Bibliography 27 



Department Bulletin No. 1088. — Zygobothria Nidicola, an Impor- 

 tant Parasite of the Brown-tall Moth: 



Introduction 1 



Distribution in the United States 2 



Life cycle of the brown-tail moth 2 



Life history and biology of the parasite 2 



Economic importance of the parasite 9 



Department Bulletin No. 1089. — Reindeer in Alaska: 



Introductory (by E. W. Nelson) 1 



Biolog^^ of reindeer 5 



Reindeer as range stock 10 



Grazing and range management 19 



Herd management 33 



Handling the herds 40 



Predatory animal enemies 52 



Injuries and diseases 52 



Parasites 57 



Pathological conditions in general 68 



Summary 69 



Check list of Alaskan range plants 70 



Department Bulletin No. 1090. — The Effects op Inbreeding and 

 Crossbreeding on Guinea Pigs: 

 I. Decline in ^^.gor: 



Eai"lier views on inbreeding 1 



Plan of the experiments 3 



History of the guinea-pig stock 3 



System of mating, care, and feed 8 



The data recorded 9 



The characters studied 9 



Indexes for growth and mortality 18 



Changes in inbred and control stocks 20 



Sex ratio 29 



Tests for disease resistance 29 



Summary 31 



Appendix — Tables 6 to 22 . .• 32 



