36 BULLETIN 824, U. S. DEPAKTMENT OF AGRICULTURE. 



Table 11. — Analysis of Pyrethrum powder (Eymard). 



Essential oil Small amount. 



Bodies soluble in ether (5.60 per cent) composed of: 



Fatty bodies (per cent) 3. 80 



Resinous bodies (per cent) 1. 80 



Bodies soluble in alcohol (94.4 per cent (sic)) composed of: 



. Brown resin (per cent) 4.80 



Plant albumen (per cent) 1. 75 



Gummy substances (per cent) 14.75 



Inulin and soluble amidon (per cent) 8.50 



Mineral salts (per cent) 7. 88 



Woody matter, by difference (per cent) 56. 72 



Total (per cent) 100. 00 



Mineral matter: 



Potassiixm chlorid (per cent) 1. 94 



Calcium carbonate (per cent) 4. 15 



Calcium phosphate (per cent) 0. 17 



Iron and silica (per cent) 1. 62 



^~ 7.88 



Thompson (273) gives the results of the analysis of a number of 

 "genuine" insect powders (Table 12). 



Table 12. — Analysis oj "genuine" insect powder {Thompson). 



Sample 

 No. 



Co'-or. 



Ash. 



Fawn 



Yellowish brown 



Light yellowish brown . 

 Light fawn 



Light yellowish brown . 



Per cent. 

 6.5 

 6.6 

 6.9 

 6.59 

 6.2 



Of two samples which contained lead chromate, one was deep 

 yellow, with 12.6 per cent of ash, while the other was dark yellow, 

 with 26.8 per cent of ash. 



Gehe & Co. (92) give the f ollov/ing results of the analysis of a sample 

 of insect powder from Dalmatia: Soluble in alcohol, 26.35 per cent; 

 insoluble in alcohol, 56.27 per cent; water, 8.45 per cent; ash, 8.93 

 per cent. As they themselves state, this analysis is worthless in 

 determining whether the sample is genuine or not. 



Hill (132), 1894, stated that genuine Dalmatian insect powder 

 has a greenish-yellow color, possesses a characteristic tealike odor 

 and a slightly bitter, aromatic taste, and shows on analysis from 8 

 to 10 per cent of moisture, and from 6.5 to 7 per cent of ash which 

 is almost entirely soluble in hydrochloric acid. 



Dieterich (69) records analyses of a number of samples of insect 

 powders, including a determination of the maximum size of the 

 particles in microns. He sets the following limits for a good com- 



