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mal life. So far as plaut life is concerned, it is luncb preferable to use 

 it in insoluble form, and used in this form we can not see that it is any^ 

 more apt to cause injury to stock. 



A series of experiments directed towards the preparation of an arsen- 

 ite of less specific gravity than Paris green, and not more insoluble 

 than London purple, would in our estimation yield good results. Soluble 

 arsenic, because of its rapid absorption by the leaves of plants and con- 

 sequent caustic effects, is useful only in comparison with other prepara- 

 tions. 



Mr. Gillette's conclusions from his experiments with arsenic are prac- 

 tically those reached by us as long ago as 1879, and as formulated in 

 Bulletin 3 of the Entomological Commission. He finds by experiment 

 that arsenic in the proportion of 1 pound to 400 gallons of water scorches 

 the tips and edges of the leaves of Apple. One pound to 8(t0 gallons 

 damaged the leaves of Plum too badly to allow this strength to be rec- 

 ommended. One ijouud to 250 gallons scorched the leaves of Grape 

 badly. One pound to 400 burnt the leaves of P>ox Elder badly. One 

 pound to 500 burnt the leaves of Honey Locust badly. Oue.pouud to 800 

 scorched the leaves of Poplar badly. One pound to 500 destroyed one- 

 half of the surface of the leaves of Easpberry, etc. American Elms re- 

 sisted the best of any plant experimented upon, while Plum was most sus 

 ceptible. With the latter tree he found that in the proportion of 1 pound 

 to 1,200 gallons of water about half of the leaves were taken oft' and the 

 remainder were left looking sickly and somewhat burnt. He concludes 

 t'hat arsenic can not be used in solution stronger than 1 pound to 1,200 

 gallons of water, and experiments show that apple leaves sprayed 

 with this solution could be fed to the larvie of Datana ministra without 

 apparently affecting them. Tests made by the chemist of the station, 

 Prof. G. E. Patrick, show that the leaves unquestionably absorb a cer- 

 tain proportion of the arsenic. Mr. Gillette expresses himself more 

 strongly against the use of this poison than any one who has yet written 

 about it. He says, "It would be unwise in the extreme to recommend 

 the latter (arsenic), especially if it be in solution, for insecticidal pur- 

 poses." 



Both the articles are timely, and we look forward with interest to the 

 results of Mr. Gillette's work. Both, however, are marred by very 

 abundant orthographical errors, i)robably the result of hasty proof- 

 reading. 



Washington and other eastern cities have been exceptionally free 

 from the attacks of shade-tree pests the past summer, particularly from 

 the defoliators, such as the Elm Leaf-beetle and the Fall Web- worm. The 

 Web-worm has been exceptionally scarce in Washington, and only late 

 in September were a few webs of the second generation observed. The 

 Ehn Leaf beetle, while rather more abundant, has been much less so than 



