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visible. Bowls, graduates, aud bisulphide were left with Mr. Taylor, 

 and all the treated hills were marked for later examination and to note 

 the effects of the chemical. The experiments were made in the middle 

 of a very hot day, the thermometer 93° in the shade, little or no wind 

 blowing, and the sand so hot that it burned through shoe soles and 

 could scarcely be handled more than a few moments at a time. Many 

 of the hills showed the edges of the leaves, when the covers were 

 removed, yellowed and set with numerous drops of a clear liquid. I 

 feared permanent injury, but instructed Mr. Taylor if he found that 

 the plants died to continue his work before the sun was high or after 

 it was quite low. He wrote me under date of July 19 : " The hills you 

 treated when here last started to grow nicely, except the two hills 

 where the carbon was poured on the ground; that killed them. The 

 treated hills showed no lice at last examination." 1 am quite satisfied, 

 from the experiments above recorded and from others that were not 

 recorded, but were simply made to settle practical questions, that in 

 melon fields at least bisulphide of carbon can be used satisfactorily and 

 effectively. It has the enormous advantage of reaching everything on 

 all parts of the plant, not a specimen escaping. With a stock of from 

 50 to 100 light covering-boxes about 18 inches in diameter, as many 

 shallow dishes, and a bottle of bisulphide the infested hills in a field 

 can be treated in a comparatively short time. 



Mr. Southwick coincided with the author of the paper in the impor- 

 tance and value of prompt i)reventive measures, and stated that he was 

 especially interested in the use of bisulphide of carbon, which he had 

 employed in his work in Central Park since 1884. He referred to a new 

 wash, a combination of bisulphide with " polysolve, " which he used in 

 the form of an emulsion. He stated, however, that " polysolve" was 

 no longer being manufactured, but thought its place might be taken by 

 kerosene emulsion. In reply to a question by Mr. Lintner, Mr. Smith 

 stated that he had made his experiments when the runners had reached 

 a length of 5 or 6 inches, and he urged a prompt use of the inse(;ticide 

 on the first appearance of the lice. Mr, Lintner suggested the use of 

 cloth coverings, in lieu of the heavier and more clumsy wooden boxes. 

 Prof. Galloway said that the formation of globules of liquid on the 

 leaves, referred to by Mr. Smith, was due to the reduction of temper- 

 ature caused by the evaporation of the bisulphide, and tliat this source 

 of possible injury might be avoided by making the applications in the 

 early morning or late in the evening, when the surrounding temperature 

 was much lower. He referred also to the protection cloth which is used 

 by seedsmen, and which is treated with oil so as to be practically air- 

 tight, and suggested its use for coverings, in lieu of wooden boxes or 

 bowls. Mr. Smith stated that some of the boxes used by him were very 



