114 MAINE) AGRICULTURAL EXPERIMENT STATION. I908. 



work by the Gypsy Moth Commission in Massachusetts it was 

 found that the Paris greens upon the market were so coarse that 

 even in the very destructive feeding of the gypsy moth, the parti- 

 cles were too large to be taken into the mouth of that insect and 

 hence it could feed upon sprayed foliage with impunity. Find- 

 ing that all of the greens on sale in Maine carried sufficient 

 arsenic, an examination of some samples was made to determine 

 the relative fineness. The results are given in the following 

 table. 



TABLE OE COMPARATIVE FINENESS OF PARIS GREENS. 



Sta. No. 



Make of 

 Paris Green. 



Particles 

 counted. 



Particles 



with 



diam. of 



19.2 or 



more 



microns 



Percentage 

 of particles 

 with diam. 

 19.2 or more 

 microns. 



Remarks. 



N.J. 10 



Adler 



2345 



16 



0.68 





Me. 3324 



Ansbacher 



1039 



58 



5.58 





Me. 3416 



Ansbacher 



463 



50 



10.80 





Me. 3419 



Ansbacher 



664 



48 



7.23 





Conn. 18509 



Barry 



4537 



14 



0.31 





Me 3417. 



Blanchard 



544 



16 



2.94 





Me. 3418 



Blanchard 



597 



8 



1.34 





N. J. 29 



Childs 



1750 



21 



1.20 





N. J. 25 

 Me. 3421 



Devo-Raynolds 

 Herrmann 



760 

 845 



137 

 34 



18.03 



4.02 



12.15% of part- 

 icle counted in 15 

 fields As O cry- 

 stals. 2 3 



N.J. 8 



Lavanburg 



1668 



51 



3.06 





N: J. 18 



Lavanburg 



963 



45 



4.67 





Conn. 18508 



Leggett 



1617 



21 



1.30 





N.J. 2 



Lucas 



1078 



58 



5.38 





Conn. 18512 



Pfeiffer 



1014 



58 



5.72 





N.J. 5 



Pfeiffer 



2229 



28 



1.26 





N.J. 21 



Pfeiffer 



1202 



94 



7.82 





Me. 3323 

 Me. 3420 



Raynolds 

 Raynolds 



641 

 360 



21 

 59 



3.28 

 16.39 



5.96% of part- 

 icles counted in 15 

 fields As O cry- 

 stals. 2 3 



7.54% of part- 

 icles counted in 15 

 fields As O cry- 

 stals. 2 3 



Conn. 18663 



Sherwin-Williams 



2196 



26 



1.18 



Many small irre- 

 gular particles. 



N. J. 28 



Sherwin-Williams 



840 



71 



8.45 





