20 BULLETIN 245, U. S. DEPARTMENT OF AGRICULTURE. 
effect is noticeable from the experiments at either New Orleans | 
or Baton Rouge. 
The cooperation of Mr. George L. Tiebout, of the Louisiana Experi- — 
ment Station, Baton Rouge, and of Mr. W. G. Taggart, of the © 
Audubon Park Sugar Station, New Orleans,-in connection with | 
these tests was of great assistance. 
As chickens and other farm animals are known to peck at, or 
consume, certain parts of manure, tests were made by Mr. E. R. 
Barber, placing hellebore-treated manure in coops with chickens — 
and using as controls chickens in a coop with untreated manure. 
Thirty-eight one-hundredths of a pound of powdered hellebore was 
mixed with 4 bushels of manure and placed in one coop with four 
chickens, and every three days another lot of the manure similarly 
treated was placed in this coop. The manure which was used 
contained fly maggots, consequently the chickens were eager to peck 
through it. In addition, the chickens, in both cases, were fed on 
cracked corn and were given fresh water. The appearance of the 
chickens was noted daily, and the test has been conducted for several 
weeks with no apparent ill effect due to hellebore. 
SUMMARY. 
The larvicidal efficiency of both inorganic and organic substances 
was tested and bacteriological and chemical examinations of horse 
manure to which many of these substances were applied are reported. 
The following inorganic substances were tried: 
Arsenical dip. Lime-sulphur. 
Chlorid of lime. Sulphuric acid. 
Epsom salts. 
Of these substances arsenical dip was the only one which when 
used in amounts considered practical destroyed the larve of the 
house fly. Because of its poisonous nature the use of arsenical dip 
as a larvicide is not recommended. 
The following organic substances were tested: 
Aniline.® Formaldehyde. 
Beta-naphthol. Nitrobenzene. 
Cresylic acid. Oxalic acid. 
Para-dichlorobenzene. Pyridine. 
Aniline, pyridine, and nitrobenzene, when used in certain dilu- 
tions, gave satisfactory larvicidal results, but the cost precludes 
their use. 
The larvicidal action of the following plant materials was tested: 
Plant material containing saponin— 
Corn cockle (Agrostemma githago). 
Agave (Agave lecheguilla). 
