1914] Glaser—Bacterial Diseases of Caterpillars 185 
tively recent times diseases occurring in the same caterpillar, but 
totally different etiologically were confused with one another. ‘The 
same name was often given to two distinct diseases and vice versa, 
the same disease was designated differently by different workers. 
Furthermore, the cultural and biological characters of the bacteria 
isolated were never thoroughly studied and hence no two investi- 
gators knew whether they were dealing with the same or different 
species. Many people untrained in bacteriology entered this field 
and helped to swell the enormous literature already accumulated 
with their inexact observations and careless experiments. Every- 
one familiar with the subject knows how difficult it is, how careful 
one has to be in drawing conclusions and how easily serious mis- 
takes are made. From a consideration of some of the more im- 
portant contributions to our knowledge of the bacterial diseases 
of caterpillars, the present condition of the subject will become 
apparent as well as the vast number of problems yet unsolved. 
Flacherie and the Clinical Picture of an Infected Silkworm. 
99 66 
The diseases known as “‘flaccidezza,” “lethargia, negrons,” 
‘mortipans,” “‘maladie de tripes,” “‘maladie de morts-blancs,”’ 
‘“maladie des morts-flats,”’ “‘schlaff-sucht,”’ “‘faulsucht,”’ “flaecid- 
ity,” ‘““schizomycosis,’” and “caterpillar cholera’? are synony- 
mous with the one known as flacherie. 
Flacherie appeared in the silk industry as an epidemic at the 
end of the sixteenth century. The larve usually contract the 
disease, which is characterized by its acuteness, after the fourth 
moult or at the time of spinning. Sick caterpillars show very few 
outer symptoms except loss of appetite and sluggishness. Some- 
times their skin becomes black but in other cases they retain a 
healthy appearance till death. Soon after death the body becomes 
soft, flabby and dark colored in twenty-four to forty-eight hours 
and is filled with a brown-black liquid which is said to contain 
many bacteria. 
« 
The Etiological Factor of Flacherie in Silkworms and Other 
Caterpillars. 
In 1870 Pasteur recognized flacherie in silkworms as a distinct 
disease capable of transmission to healthy larvee by the infection 
of their food, either with the excrement of sick individuals or with 
