173 
The genus Stilbum bas but a few victims and one representative 
among muscardiue fungi. This one is Stilbum Buqueti. Although this 
fungus is not perfectly well known, and for that reason we can scarcely 
expect to know Whether it passes all its stages on insects, still, accord¬ 
ing to Buquet, the fungus develops only on dead insects ; and, judging 
from Robin’s descriptions and excellent drawings, we must accept his 
view that Stilbum develops wdiile the insect is living, completing its 
development after the death of the same; in a word, it behaves like a 
true muscardine. 
In regard to Tarichium I have already said that this genus ought to 
follow j Entomophthora. The difficulty of making artificial cultures of 
Tarichium and the impossibility of the artificial infection of insects 
with the spores of this fungus render the study of this group of organ¬ 
isms extremely interesting. 
In the fungi noted on our list as accidentally developing on insects 
and possessing an entomogenons function, is one representative of the 
genus Cladosporium. Although the majority of the species of this 
genus are known as parasitic on plants, and Cladosporium does not ex¬ 
hibit parasitic qualities in the animal kiugdom, it is necessary to call 
attention to the one case of this kind supported by a mycologist as ex¬ 
perienced and learned as Professor Salcnsky, of Kazan. It may seem 
a little strange at first thought that a parasite as useful as Cladosporium 
parasitium , Sorok., which lives upon Polyphylla fullo , can be in a given 
case understood as only an accidentally saprophytic fungus. 
It is useless to speak of Pcnicillium as entomogeuous. Penicillium 
ylaucum , which, in the opinion of Lohde, may.be parasitic on a butterfly, 
Bryopliila raptricula , can in no sense be reckoned among the entomoge¬ 
uous fungi; and if Penicillium ylaucum does develop on dead chrysalides 
that are really attacked with muscardine it is simply as an after effect 
and a saprophyte. There is no doubt that the chrysalides of which 
Lohde speaks were already affected by another parasitic fungus before 
Penicillium ylaucum developed. 
The yeast fungi have nothing in common with the muscardiues, and 
it formerly it was possible to believe, as Bail did, that the house-fly was 
killed by a yeast fungus, we know now, after the excellent researches of 
Brefeld, that the supposed yeast is only an Entomophthora in a certain 
stage of development. * * * 
It is still necessary to mention the genus Metarhizium of which there 
are also certain representatives on our list. This new genus was estab¬ 
lished by Prof. N. Sorokin for the green muscardine, discovered by 
Metschuikoff upon the larvse of Anisoplia austriaca , and called by him 
Entomophthora anisoplice. As the characteristic^ of this fungus do not 
perfectly agree with those of Entomophthora , Professor Sorokin proposed 
to call it Metarhizium. But as Metschuikoff has since given the green 
muscardine the name of lsaria destructor, and as my long observations 
upon this fungus and a large number of pure cultures have proved to 
8139—No. 3-5 
