1880.] Destruction of Obnoxious Insects by Fungoid Growths. 577 
that infest noxious weeds and hinder their dissemination and 
- multiplication must be regarded as the friends and allies of man. 
Thus, the thistle rust, Zrichobasis suaveolens, an early stage of 
Puccinia compositarum, sometimes attacks the Canada thistle with 
- great virulence, and so impairs its vigor as to prevent the develop- 
ment of the seeds, thereby checking the propagation and spread 
of this pestilent plant. So, also, the troublesome bur-grass, 
Cenchrus tribuloides, is sometimes infested by a smut fungus, 
Ustilago syntherisme, which not only prevents the development 
of the seeds of the grass but also the annoying bur-like involu- 
cres. It may yet be found practicable to keep down this grass 
by fhe artificial dissemination of the spores of its parasitic 
fungus.” 
Among the facts pointing to a favorable issue of the proposed 
remedy against obnoxious insects, is the well-known fact that 
many insects living under wholly natural conditions are annually 
destroyed by fungi. Cook states that about twenty-five species of 
the genus Torrubia are known to be parasitic on insects.1 
Mr. Peck, in his Annual Report on the N. Y. Museum of Nat. 
Hist. for 1878, says, that “ the seventeen-year locust, Cicada sep- 
temdecim, which made its appearance in the Hudson River valley 
early in the summer, was affected by a fungus. The first speci- 
men of this kind that I saw was taken in New Jersey and sent to 
me by Rev. R. B. Post. Examination revealed the fact that.the 
Cicadas or ‘ seventeen-year locusts’ in this vicinity were also 
affected by it. The fungus develops itself in the abdomen of the 
insect, and consists almost wholly of a mass of pale-yellowish or 
clay-colored spores, which to the naked eye has the appearance 
of a lump of clay. The insects attacked by it become sluggish 
and averse to flight, so that they can easily be taken by hand. 
After a time some of the posterior rings of the abdomen fall 
away, revealing the fungus within. Strange as it may seem, the 
insect may, and sometimes does, live for a time even in this con- 
dition. Though it is not killed at once, it is manifestly incapaci- 
‘tated for propagation, and, therefore, the fungus may be regarded 
as a beneficial one. In Columbia county the disease prevailed to 
a considerable extent. Along the line of the railroad, between 
Catskill and Livingston stations, many dead Cicadas were found, 
nota few of which were filled by the fungoid mass.” 
He Fonoi ‘ 
** Fungi, their Nature and Uses,” p. 218. 
