1909] REIFF — FLACHERIE 105 
(Malacosoma americanum Fabr.) and those of various Noctuidae, but in spite of the 
presence of brown-tail caterpillars in large numbers a mortality of only two percent 
by flacherie appeared among them. It is possible that the caterpillars of this species 
on account of the larger amount of tannin which they contain, may be almost immune 
against the organisms of flacherie and it may have been only the weakest individuals 
which fell a prey to the disease. 
Whether flacherie is hereditary or not has not yet been positively established. 
Standfuss (Handbuch der palearktischen Gross-Schmetterlinge, 2. Auflage, Jena, 
1896) leans toward the latter conclusion, assuming that infected caterpillars never 
survive until the adult stage (p. 160). Experiments would, however, be necessary to 
prove this hypothesis, for as already mentioned, it has been shown that caterpillars 
affected with flacherie can pupate, later dying in that stage. And further, in my 
experiments on Junonia cenia (Journ. Exper. Zool. Vol. VI, No. 4, June 1909, pp. 13) 
this was shown where (p. 555) I referred to a pupa in which the body was decomposed 
by flacherie. It had died about six hours before the emergence of the butterfly, 
since all the parts of the specimen were entirely developed. The possibility of the 
inheritance of the disease cannot be cast aside therefore without further data. 
As to the actual primary cause of flacherie but very little can as vet be stated with 
certainty. Fischer (I. c.) thought that several species of micro-organisms (bacilli) 
are concerned in the disease, while Dr. Hofmann (Insektentétende Pilze, Frankfurt, 
a. M. Peter Weber Verlagshandlung) as early as 1891 found present in the excrement 
and body cavities of caterpillars affected with the disease, extremely small bacilli, 
innumerable schizomycetes, and more particularly small strings of micrococci. The 
relationship of these micro-organisms to flacherie are still to be elucidated by the 
investigations of bacteriologists and pathologists. 
I am especially indebted to Prof. W. M. Wheeler for many suggestions given me 
in the preparation of the foregoing account and for the encouragement he has given 
me in the work. 
Bussey Instirution, October 10th, 1909. 
