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Reddick (D.) & Crosby (C. R.). Dusting and Spraying Experiments 

 with Apples. — Cornell Univ. Agric. Expt. Sta., Ithaca, N.Y., Bull, 

 no. 369, January 1916, pp. 306-356, 14 figs,, 13 tables. [Received 

 18th March 1916.] 



Experiments carried out during 1915 in various orchards in New 

 York State showed that a mixture of an insecticide and a fungicide 

 can be applied in powdered form, using air as a carrier, with better 

 commercial results in the control of apple insects and diseases than 

 can be obtained by spraying. The dusting method cannot as yet be 

 completely substituted for liquid spraying, since no known powder 

 will destroy scale-insects, Aphids and pear psylla. Under average 

 western New York conditions good results can be obtained from a 

 mixture containing 85 per cent, of finely ground sulphur and 15 per cent, 

 of powdered arsenate of lead, the amount varying from 1*25 to 2'5 lb. 

 per tree in each application. The time of spraying does not differ 

 from that of liquid sprays, but it is also possible to make applications 

 at unusual times in order to meet special conditions. The method has 

 as yet only been thoroughly tested on apples, but there are indications 

 that its use can be extended to other crops. On some varieties of 

 grapes undiluted dust mixtures cannot be used, owing to the injurious 

 effect of the sulphur. 



Snyder (T. E.). Termites, or "White Ants," in the United States : 

 their Damage, and Methods of Prevention. — U.S. Dept. Agric., 

 Washington, B.C., Bull. no. 333, 16th February 1916, 32 pp., 

 5 figs., 15 plates. 



In the United States the three most common species of termites are 

 Leucotermes flavipes, L. lucifiigus and L. virginicus. L.flavipes occurs 

 throughout the country and has also been reported from Europe and 

 Japan. L. lucifugus is found in Texas, Arizona, Kansas, Colorado 

 and South California, as well as in the Mediterranean regions of Europe, 

 western France and Hungary. The native species, L. virginicus is 

 recorded from the District of Columbia, Maryland, and Virginia. 



The three species are similar in habit, being subterranean wood- 

 destroying forms. Nests are made in the wood of dead trees, stumps, 

 or decaying logs, or in underground passages beneath wood or other 

 vegetation. The nests are temporary structures, there being seasonal 

 changes in the life of the colony. The burrows of other wood-boring 

 insects are often enlarged and inhabited by termites. The centre of 

 activity of the colonies varies with chmatic conditions. In dry 

 regions the burrows are deep, and in the summer the more exposed 

 galleries are vacated for the deeper portions. In northern Virginia, 

 life from late October to early March is entirely below ground. When 

 conditions become unfavourable, the nest is abandoned and a new 

 site found. A mature colony contains several thousand individuals ; 

 an incipient colony is small and the increase in numbers is slow. 

 Newly-hatched larvae are similar in appearance and may develop 

 into soldier, worker, or reproductive forms. The young are often 

 kept in an undifferentiated state and can be changed rapidly into 

 supplementary reproductive forms of both sexes if necessary. The 

 development of the soldiers and workers is completed in less than a 



