DESTRUCTION OF FLY LARVH IN HORSE MANURE. 19 
two experiments and are therefore to be regarded as only tentative. 
However, the results of the cage experiments are in general agreement 
with the findings as given in the diagram. 
It will be noted that the highest larvicidal effect was obtained with 
borax, using 1 pound to 8 bushels. The least expensive treatment 
was that with 0.62 pound of borax, although the larvicidal action was - 
only 90 per cent. The next cheapest was hellebore, which costs 54 
cents for one-half pound of the powdered roots, and the average of 
12 experiments showed a larvicidal action of 95.5 per cent. The 
hellebore treatment at the foregoing rate costs more than that with 
0.62 of a pound of borax but shows a greater efficiency. 
In comparing the cost we have assumed that borax can be obtained 
at 5 to 6 cents per pound in 100-pound lots and that hellebore can be 
purchased at 11 cents per pound in like amounts. The price of both 
is subject to considerable variation. The results in general indicate 
that the larvicidal action varies with the amounts used, except in the 
case of nitrobenzene, where the value seems to depend on the pro- 
portions of nitrobenzene and soap in the emulsion. 
It will be noted that pyridine and aniline, when used in amounts 
sufficient to kill a high percentage of the larve, are quite expensive, 
and for this reason their use can not be considered practical. 
APPLICATION OF HELLEBORE TO MANURE. 
Powdered hellebore should be mixed with water at the rate of 
one-half pound to 10 gallons and the solution thoroughly stirred 
and allowed to stand for several hours in a barrel or other container. 
In order to obtain the most satisfactory results, the manure should 
be sprinkled with the foregoing solution immediately on removal 
from the barn. The sprinkling may be done with a watering can or 
similar device, using 10 gallons to 8 bushels of manure, taking care 
that all of the hellebore comes in contact with the manure and paying 
particular attention to the outer edges of the pile. In estimating the 
amount of solution to be employed it may be assumed that 2 bushels 
of manure per horse is the daily output of the stable. This is a liberal 
estimate, and in many stables the daily output is much less. 
EFFECT OF HELLEBORE ON PLANTS AND CHICKENS. 
During November, 1914, a series of tests was started at both 
Baton Rouge and New Orleans, La., to determine whether hellebore, 
when applied in considerable amounts, exerts injurious effects on 
plant growth. The plants grown included cabbage, lettuce, oats, 
turnips, radishes, potatoes, wheat, and mustard, half of each plat 
being fertilized with hellebore-treated manure, and the other half 
recelving untreated manure. At the present time no injurious 
