Pere ee a 
416 MINNESOTA STATE HORTICULTURAL SOCIETY. 7 
eye, but the microscope alone can give us an explanation of the ; 
whole process. : 
Being afraid that by this time you will be thoroughly sick of the b 
Empusa,I will notinflict upon your patience the microscopic history 
of the influenza, another disease that attacks our poor domestic fly. 
It goes by the name of Jsaria, was first discovered by Meigen, and 
has but one good point about it—it kills flies. 
To wind up this already lengthy discourse upon diseases of flies, 
let me only mention some other enemies—besides yourselves—of 
this troublesome intruder to an afternoon’s snooze knowing that it 
will please you to hear that the life of a fly is far from being an 
eternal round of constant revelry and pleasure, but that it is also 
troubled in more than one way. Besides several true worms (Nem- 
etodes),it is preyed upon in Europe by two kinds of ichneumon flies 
whose larve feed inside of its host, also by a fly-parasite (Astoma 
parasiticum). It is a pity that these useful parasites have not as 
yet been introduced into this country. We possess, however, already 
one fly-parasite in this country (Astoma musearum). You all have, 
no doubt, seen small red dots upon the base of the wings of our fly. 
This red dot is the parasite just mentioned, and let us hope that it 
may increase at the same ratio as all his relatives are in the habit of 
doing. Of course we all include 
“‘Mosquito, old back-bent fellow, 
In frugal freize coat drest,” 
in the wish expressed above, and itis a great satisfaction that an- 
other species of Empusa attacks it. Good speed to it! 
IRRIGATION IN MINNESOTA. 
There is such a dearth of water during the dry seasons these 
years and when our agricultural and forest crops most need it, re- 
sulting in poor harvests, that the matter of irrigating our farms and 
gardens must be considered. Necessity drives us to provide some 
way by which the surplus water in the spring, usually rushing in 
destructive floods and reacting into severe drouths,can be conserved 
and economically distributed. The state legislature has not esti- 
mated geodetic surveys as of practical importance enough to have 
them done ou the scale which our necessities demand. It is certain 
that were all the water falling from the clouds and gushing from 
the springs and running to waste, harbored in ample reservoirs at 
or near our numerous watersheds, and thence made to flow over our 
lower lands, under proper management, the uncertainty and cank- 
ering anxiety about our crops and trees would be ended, and their 
abundance increased almost beyond measure. Where the reservoirs 
should be established, will have to be determined by competent 
surveyors. 2 
IRRIGATION IN EASTERN MINNESOTA. 
It is believed the water-falls on the St. Croix, St. Louis, Mississippi 
and their tributaries, can be so controlled by dams and canals as to 
supply a large proportion of the farms in the eastern part of the 
state. 
