CONTENTS. 3 



Department Bulletin No. 405. — Lupines as Poisonous Plants: page. 



Part I. — Introduction 1 



Summary of knowledge of lupines as poisonous plants 1 



Distribution of lupines 4 



Common names of lupines 4 



Alkaloids of lupines 5 



Ictrogen 6 



Part II. — Experimental work 7 



Pharmacological investigations by Sollmann 7 



Field experiments with lupines IS 



Laboratory experiments with extracts of lupine seed upon mice 25 



Part III. — -Discussion of general conclusions 28 



Failure to poison sheep in 1910, 1911, and 1912 28 



Lupine not a cumulative poison 29' 



Toxicity of different species of lupine : 30 



Toxicity of lupine for sheep 30 



Toxicity of lupine seed for sheep 31 



Toxicity of lupine pods for sheep 32 



Toxicity of lupine fruit for sheep 32 



Symptoms 33 



Pathology 36 



Comparison of ' ' lupinosis " and poisoning of sheep by American lupines 36 



Remedies 38 



Range conditions under which sheep are poisoned 39 



Treatment of range animals to avoid poisoning 41 



Summary 42 



Literature cited 42 



Department Bulletin No. 406.— Distinguishing Characters of the Seeds 

 OF Sudan Grass and Johnson Grass: 



Introduction 1 



Distinguishing characters of the seeds of Sudan grass 3 



Distinguishing characters of the seeds of Johnson grass 4 



Apparent exceptions to the distinguishing characters described 4 



Department Bulletin No. 407. — Progress Reports of Experiments in 

 Dust Prevention and Road Preservation, 1915: 



New experiments 1 



Experiments on Mount Vernon Avenue Road, Alexandria County, Va. . 2 



Experiments on Falls Road, Montgomery County, Md 24 



Experiments on Bradley Lane, Montgomery County, Md 30 



Experiments at Washington, D. C 32 



P^xperiments at Buena Vista, Fla 35 



Experiments at Jupiter, Palm Beach County, Fla 38 



Experiments at West Palm Beach, Fla 40 



Experiments at Ocala, Fla 41 



Supplementary reports on experiments previously reported 45 



Supplementary report of experiments at Lemon City, Fla., 1914 45 



Supplementary report of experiments at West Palm Beach, Fla., 1914. . 46 



Supplementary report of experiments at Miami, Fla., 1913 47 



Supplementary report of experiments on Rockville pike, Montgomery 



County, Md . , 1 9 J 3 48 



Supplementary report of experiments at Washington, D. C, 1912 55 



Supplementary report of experiments at Chevy Chasf^, Md., 1912 57 



Supplementary report, of experiments at Chevy Chase, Md., 1911 60 



