4 DEPAETMEInT of AGEIGULTUEE BULS. 426-450. 



Depaetment Bulletin No. 430. — Cebeal Experiments on the Cheyenne Page. 

 ExPEEiMENT Farm, Akchee, Wto. 



Description of the district 2 



Cheyenne experiment farm 8 



Experiments witli wheat 12 



Experiments with emmer and spelt 25 



Experiments with oats 26 



Experiments with barley 30 



Experiments with flax 33 



Experiments with minor grain crops 86 



Summary 38 



Department Bulletin No. 431. — Sacbeood. 



Historical account 2 



Name of the disease 4 



Appearance of healthy brood at the age at which it dies of sacbrood 6 



Symptoms of sacbrood 10 



Cause of sacbrood 24 



Weakening effect of sacbrood upon a colony 30 



Amount of virus required to produce the disease, and the rapidity of 



Its increase 31 



Methods used in making experimental inoculations 32 



Means for the destruction of the virus of sacbrood 34 



Heating required to destroy sacbrood virus when suspended in water 34 

 Heating required to destroy sacbrood virus Avhen suspended in 



glycerin 35 



Heating required to destroy sacbrood virus when suspended in honey_ 36 



Resistance of sacbrood virus to drying at room temperature 37 



Resistance of sacbrood Tirus to direct sunlight when dry 38 



Resistance of sacbrood virus to direct sunlight when suspended in 



water 39 



Resistance of sacbrood virus to direct sunlight when suspended in 



honey 40 



Length of time that sacbrood virus remains virulent in honey 40 



Resistance of sacbrood virus to the presence of fermentative processes 41 

 Resistance of sacbrood virus to fermentation in diluted honey at out- 

 door temperature 42 



Resistance of sacbrood virus to the presence of putrefactive proc- 

 esses 43 



Resistance of sacbrood virus to carbolic acid 44 



Modes of transmission of sacbrood 46 



Diagnosis of sacbrood 48 



Prognosis 49 



Relation of the.se studies to the treatment of sacbrood 50 



Summary and conclusions 52 



Department But.letin No. 432. — The Spike-horned Leaf-miner, an 

 Enemy of Grains and Grasses. 



Synonymy 2 



History of the species 2 



Food plants 3 



Description 5 



Distribution 7 



Injury to plants by adults puncturing the leaves 7 



Injury to plants by mining habits of larvse _ 8 



Life, history 9 



Rearing methods 14 



Parasitic enemies 15 



Preventive measures ^ 16 



