X 
Journal of Agricultural Research 
Vol.IX 
Influence of Crop, Season, and Water on the Bacterial Activities 
of the Soil 
Page 
Fig. i. Plan of plots 30G to 50G, Greenville farm, showing main flume and 
laterals. 303 
The Pink Bollworm, Pectinophora gossypiella 
Fig. i. Pectinophora gossypiella . 347 
2. Pectinophora gossypiella . 348 
3. Cotton boll infested with Pectinophora gossypiella . 351 
4. Plan of the house used for observations on the behavior of the moths of 
the pink bollworm in relation to light. 356 
5. Pyroderces rileyi: A t Venation of forewing; B, venation of hind wing.. 363 
6. Pyroderces rileyi: A, Head capsule of larva from front; B, head cap¬ 
sule of larva from side. 364 
7. Pyroderces rileyi: Right mandible of larva. 365 
Toxicity of Various Benzene Derivatives to Insects 
Fig. i . Curves showing periods of time required to kill with different quantities 
of the different benzene derivatives. 374 
2. Graph showing the millionths of a gram-molecule necessary to produce 
the death of five house flies in a i-liter flask at 70° F. in 400 minutes. 374 
3. Curves showing the relationship between boiling point of the compound 
and its toxicity expressed in millionths of a gram-molecule. 377 
4. Graph showing the quantity of the benzene derivatives necessary to 
saturate 1,000 cubic feet of space at 70° F. and the time required by 
such quantity to kill house flies. 379 
A New Strain of Rhizoctonia solani on the Potato 
Fig. 1. Camera-lucida drawings of mycelium of the Rx and R 5 strains from the 
same medium and culture of the same age. 416 
2. Camera-lucida drawings of short sclerotial cells of the Ri and R 6 strains 
from cultures of the same age grown on the same medium. 417 
3. Camera-lucida drawings of germinating sclerotial cells of the R 7 and R 5 
strains, 
4i7 
