161 
the vapors which penetrate fabrics so well and kill insects so thor- 
oughly would act in the same way upon the microbes which engender 
epidemics.* 
In discussing this paper Mr. Atkinson stated that he had used a 
very similar box in fumigating objects infested with insects. 
Mr. Garman called attention to the fact that at the museum of com- 
parative zoology at Cambridge a large upright zinc-lined case was con- 
stantly used for disinfecting the skins of birds and mammals. 
Mr. Riley had used bisulphide of carbon successfully for his insect 
collections. 
Mr. Smith had used it successfully for ants, and found it not injurious 
to vegetation. 
Mr. Garman reported having found it effective in destroying the 
Melon Louse. His method of applying it was to roll the vines up in a 
heap, then invert a tub over them, and after placing a saucer containing 
a tablespoonful of the bisulphide under the tub its edges were pressed 
down into the soil or the earth was drawn up when necessary. He had 
tried the fumes of burning sulphur and tobacco, but the former injured 
the plants and the latter did not kill the plant lice, many of them 
gradually recovering after being stupefied by it. 
Mr. Smith thought since the aphides often spread from particular 
plants or hills, the use of bisulphide in good season might make it pos- 
sible to prevent the injuries of these insects. 
Mr. Forbes, who had been prevented by his duties as presiding officer 
from taking part in the discussion on parasitism when this subject was 
before the association, was called on to give his views on this subject. 
The gist of his remarks was that parasites and hosts keep a pretty 
constant ratio to each other when in natural conditions. Under dis- 
turbed conditions he thought the practical view is that parasites are 
beneficial. 
The following paper was then read : 
APHELENCHUS OLESISTUS NOV. SPEC, A NEMATOID WORM, CAUSE 
OF A LEAF SICKNESS IN BEGONIA AND ASPLENIUM. 
By Dr. J. Ritzema Bos, Wageningen (Netherlands). 
(Eead, in the author's absence, by G-. F. Atkinson.) 
In the report of the third annual meeting of the Association of Eco- 
nomic Entomologists (Insect Life, Yol. iv, p. 31) Prof. G. F. Atkin- 
son gives some information on a species of Aphelenchus, discovered by 
Dr. Byron D. Halstead in the leaves of sick plants of Chrysanthemum 
and Coleus. Prof. Atkinson says of the effects produced by this para- 
*Note. — I have observed in bisulphide of carbou no clearly defined power of tak- 
ing out the colors of fabrics which I have subjected to its vapor. It may, there- 
fore, be used without fear, except, perhaps, in the case of the most delicate tints. 
