
tae ys ee 
fed on sugar syrup and distilled water. At the Experiment Station (200 
feet) 47 of the adults died between August 31 and November 23. At the 
1,000-feet area 37 adults died between September 24 and November 16% 
at the 1,800-feet elevation only 13 adults hdve died between September 
6 and November 23. These observations demonstrate that the adults live 
longer at higher elevations when the temperature is lower." 
The experiments by H. H. Richardson, of the greenhouse at Washing- 
ton, D. C., on the control of the common red spider mite (Tetranychus 
telarius L.) with pyrethrins, nicotine, and rotenone, as thus far con— 
ducted, are summarized briefly as follows: "Without the addition of 
some 'wetting' agent, the pyrethrins, rotenone, and nicotine were rela- 
tively inefficient, even at high concentrations, for the control of the 
greenhouse red spider mite. With the addition of potassium oleate soap 
(0.25 per cent, 1-400) rotenone was slightly more toxic than the pyre- 
thrins; nicotine was much less potent than either of the other two. 
Soap appeared to be a more efficient wetting agent than sulphonated 
castor oil for the pyrethrins and rotenone; with nicotine the reverse 
appeared to be true. Hydrogen—ion studies indicated that when these 
materials were added to diluted spray solutions, the pyrethrins (in 
alcoholic extracts) had a distinctly acidic effect, rotenone (in ace- 
tone solution) had relatively slight effect; nicotine (chemically pure) 
had a distinctly alkaline effect." 
The following summary has been prepared from a report made by 
Oliver I. Snapp, dealing with extensive experiments conducted at Fort 
Valley, Ga., in the control of the peach borer (Synanthedon exitiosa 
say) with paradichlorobenzene dissolved in cottonseed oil and in mineral 
oil, respectively, and then emulsified and applied as a spray to the base 
of the tree. The emulsion was used in such quantities that the amount 
used on each tree was equivalent to that ordinarily applied in the form 
of crystals. The paradichlorobenzene applied in an emulsion at strengths 
up to one-half ounce of the chemical per tree on l-year and 2-year 
trees, and up to three-fourths of an ounce per tree on 35-year-old 
trees, caused no injury. On 6-year-old trees, with a dosage of one ounce 
per tree, no injury occurred except one or two small spots where the spray 
had puddled. The usual crystal treatments, on the other hand, caused 
severe injury to l-year, 2-year, and 3-year-old trees. When mineral 
oil was used as a carrier, a little injury occurred with a dosage of 
three-fourths ounce of paradichlorobenzene on S-year-old trees. Where 
the tree trunks were mounded after being sprayed the emulsions gave a 
kill of borers equivalent to that obtained with the standard crystal 
treatment with equal quantities of chemical. When the trees were not 
subsequently mounded the borer control was comparatively poor. The emul- 
Sion treatment appears to offer a safe method of treating young trees, 
whereas such trees are frequently injured by the standard crystal treat-— 
ment under Georgia conditions. 
Mr. Snapp reports continued satisfactory results in the control 
of the lesser peach borer (Synanthedon pictipes G. & R.) from the use of 
