55 
. 
of sterigma (Sterigmenbiindel) spring from these, and bear the above- 
mentioned green spores. After two or three weeks the whole body 
of the insect is converted into a heap of dusky green spores. Sev¬ 
eral of the attempts made to infect Anisoplia larva? with these green 
spores were successful, while in a few cases the grubs remained 
healthy for a long time. The results were in all respects the same 
as those in DeBary’s experiments with Isaria farinosa . Anisoplia 
larvae killed by the green muscardine have now been found in widely 
separated regions of Southern Russia. I have also found the disease 
attacking another injurious insect among us, the turnip beetle 
(Cleonus punctiventris). During the present summer the green mus¬ 
cardine appeared among these beetles as a destructive epidemic. It 
attacks the adult insect, as well as its eggs, larvae, and pupse. By 
August, at a time when the epidemic had not yet run its course, 
about forty per cent, of the entire generation of this year of Cleonus 
punctiventris was destroyed by it. All attempts at infecting these 
beetles, especially their larvae, resulted fortunately. Ninety Cleonus 
larvae, which were brought in contact with muscardine spores for a 
short time, all died in the course of twelve days. Upon many of 
these one could very easily follow the germination of the spores, 
j! The deadly effect of the disease began to show itself on the fifth 
day after the infection, which short period was apparently explained 
by the thinness of the cuticle of the larvae. Of the number men¬ 
tioned above, sixty-two died of muscardine, and twenty-eight from 
other causes, in part of pebrine. Upon the beetles the muscardine 
worked somewhat more slowly, but with equal certainty. Fifty-eight 
recently transformed beetles were infected, and in the course of 
fifteen days fifty-two were dead of muscardine, and six of other dis¬ 
eases. The largest number died on the seventh day. These, to¬ 
gether with many other experiments and observations, justify the 
conclusion that Isaria destructor really produces an epizootic among 
the injurious insects mentioned, similar to that which Botrytis bassii 
produces in the silk-worm. This comparison to the fungus just 
mentioned is all the more appropriate since Cleonus punctiventris is 
likewise subject to a disease produced by this same Botrytis. The 
white muscardine I could find only upon hibernating beetles, never 
upon their larvae or pupae, or upon imagos recently transformed. 
When I had reached the results above described, I thought it pos¬ 
sible to spread the green muscardine artificially by sowing spores. 
* * * In order to procure the necessary quantity of 
spores with which the earth inhabited by the grubs and Cleonus 
larvae must be sown, it was at first important to find some medium 
in which the fungus could be cultivated outside the body of the in¬ 
sect. I easily succeeded in finding a method by which to induce 
this insect fungus to send out long runners, which formed a true 
mycelium. For this it was only necessary to bury in moist sand 
insects which had died with muscardine, and to leave them there a 
fortnight. It was much more difficult, however, to induce the growth 
| of the fungus in organic fluids. It was indeed easy to cause the 
Isaria destructor to produce new spores in a hanging drop of sugar, 
but for a long time I did not succeed in this experiment upon a 
larger scale. I am very much indebted to my colleague, Mr. A. We- 
rigo, professor of chemistry in Odessa, that he first called my atten- 
