126 INJURIOUS INSECTS OF I9Q09Q AND IQIO. 
indicated, is made of panes of glass, which slip into grooves, strips 
of felt making these glass doors (for such they are) tight. Fig. 
73 shows a practical form of breeding-cage, also made use of by 
Mr. Urbahns; namely, large flower-pots under which any host 
material, other than a growing plant, can be placed. Upon the 
inverted flower-pots are placed glass chimneys, as indicated, into 
which ascend insects emerging and seeking the light. A board 
base, containing ventilators covered with fine copper gauze, may 
be used where collections of green materials are inserted. 
In the experimental garden much work was done, in 19009, 
against stalk-borers, see page 85, and in both 190g and 1IgIOo, 
various vegetables were planted for experimentation. The garden 
contained, in I910, peas, beets, carrots, tomatoes, tobacco, corn, 
potatoes, cucumbers, clover, alfalfa, wheat, melons, sorghum, flax, 
beans, plum and apple trees. 
The object of this garden was: 
1. To have all these plants on hand as they were needed for 
insects in experimental work. 
2. To carry on preliminary experiments in combating insects 
attacking these different crops. 
3. To keep in touch with the different pests attacking each 
crop. 
Sorghum was planted for the sole purpose of trying to see if 
Contarima sorghicola would attack the seed. Melons were planted 
to watch Aphis gossippi, with hopes of getting notes on egg-laying 
habits. On potatoes, notes were taken on preliminary sprayings. 
A few experiments were tried with insecticides, notably against 
the potato beetle, with both Paris green and arsenate of lead. This 
work was carried on by Mr. Stafford. We are hardly justified in 
forming absolute conclusions from the following results: 
1. Potatoes sprayed with arsenate of lead, 1 pound to 50 gallons. Results: 
Considerable reduction in number of larvae. 
to 
Potatoes sprayed with arsenate of lead, 2 pounds to 50 gallons. Very few 
living larvae present. 
3. Potatoes sprayed with arsenate of lead, 4 pounds to 50 gallons. Results: 
About the same as in two preceding experiments. 
4 Potatoes sprayed with Paris green, 1 pound to 50 gallons. Results: “But 
little improvement. Many living larvae.” 
5. Potatoes sprayed with Paris green, 2 pounds to 50 gallons. Very few 
potato beetles alive, 
