UNITED STATES DEPARTMENT. OF AGRICULTURE 
Contribution from the Bureau of Entomology 
L. O. HOWARD, Chief 
Washington, D. C. ~ PROFESSIONAL PAPER February 26, 1920 
EUROPEAN FOULBROOD 
By G. F. WHITE 
Specialist in Insect Diseases 
CONTENTS 
é Page Page 
eto du Colon vcs eu alee a 1 | Resistance of Bacillus pluton to fer- 
Name of-the disease_____-__-___-- 2 mentation==2= 2a se BB BSA 8h Pal 
Healthy larve of the age at which Resistance of Bacillus pluton to 
they die of European foulbrood_- 3 PUtKeLaAChlOne ===. 2 eee ee ee 22 
SSSA AtN) 9170) 0a a gpa eh Se gees 4 | Viability of Bacillus pluton in honey _- 23 
BY OL O Sayan ss aie SA as Se 7 | Viability of Bacillus pluton in pollen_. 24 
Mechniques sa 2 weiss sae 15 Resistance of Bacillus pluton to car- 
Thermal death point of Bacillus Dollie esaci diss esses re ee 24 
TOUVCE O10 eae i a eee oe ee ee lp iL?) Effect of drugs on European foul- 
Resistance of Bacillus pluton to Joy oYoYG | eae Cy deed Pp Ale Bele es RS Ae oe 2 26 
GD ig y si To a el ee se a 17 Transmission of European foulbrood_ 26 
Resistance of Bacillus pluton when Diagn OSS) =e = as eee ete so 28 
dry tovdirect ‘sunlight2=—- 22222 "3% 19 PPOSnOSIS (2 aa ee eee Sil 
Resistance of Bacillus pluto» in Summary and conclusions__—______- 31 
water to direct sunlight_________ 20 Ititeratunemcitede == -2 3.2 es eee 34 
Resistance of Bacillus pluton in Explanation of plates_.__-________ 37 
honey to direct sunlight_______-_ 21 
INTRODUCTION 
European foulbrood is an infectious disease of the brood of bees 
caused by Bacllus pluton. It is characterized by the death of brood 
during its uncapped stage and by the absence of any marked odor. 
The disorder has a wide distribution and is fairly well known to bee- 
keepers. The losses sustained by the infected apiary vary from a 
slight weakening of the colonies in some instances to the destruction 
of all of them in others. 
Practical apiarists have determined mucn concerning the disorder 
while pursuing their profession. The writer in an earlier paper (15)+ 
referred to the nature and extent of the progress that had been made 
in the study of the disease from the laboratory point of view. The 
present paper deals with results which have been obtained from a con- 
tinuation of the work. Among the problems considered are: The re- 
1 Wigures in parentheses refer to ‘‘ Literature cited,” p. 34. 
132817° —20— Bull. 810 ——1 
