SCIENCE AND INDUSTRY. 
INSECT PESTS IN WHEAT. 
In the Review of Applied Entomology of November last an abstract 
is published of the methods for dealing with weevil-infected wheat. 
Owing to shipping difficulties, arising out of war conditions, wheat has 
had to be stored for an unusual length of time in Australia. No pro- 
visions had been made for the accumulation of such large quantities, and 
ample opportunities were thus afforded for infestation by weevils and 
other insects. In grain eventually shipped to California the following 
beetles were found:—Calandra oryzae, C. granaria, Tribolium confusum 
(confused flour beetle), 7. castaneum (ferrugineum), Silvanus suri- 
namensis (saw-toothed grain beetle), Rhizopertha dominica (lesser 
grain borer), Lamophloeus minutus (flat grain beetle), and Vene- 
broides mauritanicus. The cosmopolitan parasite of grain weevils, 
Mesaporus calandraw, Wow., was also very abundant. On arrival at 
San Francisco some of the sacks had as much as 80 to 90 per cent. of 
their contents injured by weevils. The grain was taken straight from 
the docks to the mills, where it was passed through the usual screens to 
remove the straw, unthreshed heads, and other rubbish. Before use it 
passed through suction cleaners, that draw off the light grain, weed 
seeds, weevils, &c. These screenings, if containing very many beetles, 
were burned, but if a good deal of grain were retained, were used as food 
for pigs, sheep, or poultry. All mills handling this infested wheat were 
urged to make some provision for the destruction of the insects. Experi- 
ments made show that exposure to heat, with a steam pressure of 80 to 
150 pounds, for twelve hours, killed all the beetles. Various kinds ot 
boxes and rooms were equipped for this purpose. In some cases the 
wheat was sprayed by means of hand-pumps with carbon tetrachloride 
at the rate of 2 U.S. gallons of liquid to 30 tons of the grain. Wheat 
treated in this way is not injured, and if the bins are tightly closed for 
at least two or three days, all weevils in, them will be found dead. 
PROPERTIES OF DERRIS. 
Experiments on the properties of Derris as an insecticide are 
described in the current number of the Review of Applied Entomology. 
Though commonly known as Derris, the correct botanical name of plants 
of this genus, which belongs to the Papilionacew, is Deguelia. They are 
found throughout the tropics, but are more abundant in the Old World 
than in tropical America. These plants have long been known as fish 
BOO nes for which purpose the roots are pounded into a pulp. Although 
erris may prove useful as a contact insecticide and as a stomach poison, 
it is of no value as a fumigant. As the material must be imported, only 
dried roots and stems are available. Tesis were made with petroleum 
ether, ether, chloroform, alcohol, and water as solvents, and the results 
show that petroleum ether is a poor solvent, while the others may be 
considered good, though only aleohol and water can be regarded as 
economically useful, the best results being obtained with denatured 
alcohol. Details are given of the experiments made with various species 
of Deguelia. Alcoholic extracts of D. elliptica, D. uliginosa, and D. 
koolgibberah were generally efficient, while those of D. oligosperma, D. 
scandens, and D. robusta were only seldom so; the powder of an uniden- 
tified species mixed with water or soap solution was usually efficient, 
while the other powders tested by this method were found ineffective; of 
76 
