Ill 
loosely constructed, and in these cases the 2 ounces of bisulphide used 
had not been effective against the lice. Mr. Howard stated that Gar- 
inan's original suggestion of the use of a washtub which would inclose a 
vine of considerable size by drawing in the runners was a very practi- 
cal one, especially in the case of small garden patches. Mr. Smith 
urged the advisability of very prompt action in the case of the melon 
louse, instancing the comparative ease with which it could be stamped 
out when it lirst appeared on young plants having but three or four 
leaves. This, he said, would require a very much smaller covering and 
less bisulphide. He also thought it possible that paper boxes could be 
obtained veiy cheaply in nests, and could be employed to inclose the 
vines. Mr. Saunders said that paper caps were made for the use of 
farmers, to protect their haycocks, and he thought the same factories 
would make smaller caps for the use suggested by Mr. Smith, and prob- 
ably at a very slight cost. In reply to a question by Mr. Hopkins as to 
the effect of bisulphide on the natural enemies of the Aphis, Mr. Smith 
replied that he placed no importance whatever on the action of natural 
enemies, and was quite indifferent as to the effect of the applications 
on them, believing that natural enemies were rarely, if ever, of any 
economic importance, or appeared in numbers sufficient to keep injuri- 
ous insects in check until after the main damage had been done. Mr. 
Marlatt referred, in this connection, to the frequent receipt by the 
Department of Agriculture, during July of the present year, of samples 
of leaves of melon covered with aphides, which were in every instance 
so extensively parasitised that scarcely an unaffected louse could be 
found; and he urged that this seemed to be a case of very substantial 
benefit accruing from the presence of parasitic enemies. 
Mr. Smith again stated that the parasite was, generally speaking, 
too late in its appearance, and that great injury was always done 
before any effective stay in the multiplication of the pest was brought 
about. 
Mr. Howard said that one practical point, at least, resulted from 
the presence of the parasite as described on the samples referred to, 
and that was that it obviated the necessity of detailing any remedial 
treatment in reply to correspondents sending such samples, it being 
only necessary to state that by the time the reply was received the 
insect pest would have been entirely exterminated by the parasite. 
Some general discussion of the relations of parasites to injurious 
insects followed. Mr. Howard wished Mr. Smith, in his future work, 
to note the exact temperature and the effect of heat on the aphides, 
referring to the occasional sudden destruction of these insects by the 
very warm July days in Washington. 
Mr. Saunders suggested experimenting to determine the relative 
effect on plants of rapid evaporation of bisulphide on hot earth or 
sand, or the probably slower evaporation on cool soil, or the still 
slower evaporation in graduates. 
