281 
A EUROPEAN WHITE GRUB FUNGUS. 
In the Comptes Rendus of the 3d of August, 1891, M. Alfred Giard 
has given a summary of our information upon this interesting fungous 
disease of the larve of the European Cockchafer. He states that this 
disease was first observed in epidemic form in Normandy in 1866, and 
was again discovered in Germany in 1869. Since the latter year it has 
been found more or less commonly all through northern France. It 
should be known scientifically as Isaria densa Link, this name having 
priority over Botrytis tenella Saccardo. The disease communicates 
itself readily from one White Grub to another, and can be transmitted 
equally well by inoculation or by aspersion to insects of different or- 
ders, but the infested insects produce the spores spontaneously only 
when they live underground or in a humid condition. Under contrary 
conditions the hyphas and the spores can be obtained by placing the 
mummified insects in a moist chamber. The fungus can be easily cul- 
tivated, not only upon meat, as the old observers have stated, but also, 
as M. Giard was the first to show, upon the most variable solid or liquid 
media. These cultures can be made at all seasons, and the dried spores 
will retain their germinating capacity for more than a year. The fun- 
gus can be experimentally communicated to the Silk-worm, but there 
are few chances for this disease to occasion epidemic in the magnaner- 
ies, for instead of easily producing efflorescences and spores, as in worms 
infested with muscardine, the worms mummified by [saria densa remain 
in the sclerotic condition until they are placed in a moist chamber. 
The author has indicated how, with liquid cultures properly diluted 
or with a mixture of spores and dried earth, the grub can be readily 
reached and infested at the moment when it rises to the surface of the 
ground. He considers this method of utilizing the fungus much more 
practical than those suggested by MM. Prillieux and Delacroix, and 
less complicated that those suggested for the use of other cryptogamic 
diseases by MM. Brefeld, Cienkowsky, Metschnikoff, and others. He 
has great confidence in the employment of this fungus to reduce the 
damage caused by the White Grub to the minimum, and believes that 
_ agriculturists will be able to arrive at this important result without 
great expense. He claims the priority for this suggestion, and he ac- 
cepts the responsibility of all that he has said both in this paper and ina 
former one relative to the destruction of the White Grub by Isaria, but 
he reserves his opinion upon the possible employment of this fungus 
against other injurious insects, and particularly apaiey those which 
live in the open air or in dry places. 
We have already mentioned in these pages (Vol. Iv, p. 152) the fact 
that a French firm has commercially adopted the use of this eryptogam, 
and it will be noticed by comparison that the method recommended 
differs from the one suggested by M. Giard. 
Some discredit is cast upon the practical utility of this method by 
