222 



5f the body, nor could any mode of teasing the insect induce an aug- 

 mentation or diminution of light from the last. 



" The Pyrophorus has a habit, before it becomes jaded, of throwing 

 itself up from the ground or other surface when placed upon its back, 

 by a spring or jerk of the head downward, and can throw itself to a 

 height of six or eight inches. I found the combined light of eighteen, 

 in a two-ounce vial, sufficient to enable me to read a newspaper, as one 

 could desire to do in a public assembly." 



In answer to a request for liviug specimens, Mr. Moore replies that 

 those he confined died in less than thirty-six hours. 



PoKE-KOOTPOR DESTEOYiNG INSECTS.— Dr. F. C. Eeuuer, of Frederick 

 County, Maryland, writes to the Department that several years ago he 

 collected some poke-root (P//2//o?«cca decandra) for medicinal purposes, and 

 placed it at various places about the house, to dry. After several days 

 he observed that there were many cockroaches lying dead, and upon ex- 

 amination found they had been partaking freely of the poke-root. Some of 

 the root was placed near their haunts, and the result was that it rid the 

 premises of those insects. Since then he has communicated the remedy 

 to others, who have tested it with satisfactory results. 



We have not yet had an opportunity of trying the efficacy of the root 

 as an insecticide, but shall test it in the spring. Should any of our cor- 

 respondents have experimented with it, they will oblige us by giving 

 the result of their experience before we venture to recommend it for 

 general use. 



CHEMICAL MEMORANDA. 



By W3I. McMuRTRiE, Chemist. 



This Department has received from Messrs. Geo. R. Hill & Co., Alex- 

 andria, Va., a sample of offal from their hominy mills, with the follow- 

 ing communication : 



Eecent experiments by farmers in Connecticut and New Jersey having determined that 

 corn-meal is a most valuable fertilizer, (equal in some cases to guano,) we have the honor to 

 forward this day, by express, a specimen of the offal from our hominy mills, composed prin- 

 cipally of the hearts or germs of the corn, and hence believed to be the more valuable, (as 

 the phosphatic element so largely predominates, ) and respectfully ask that you will cause 

 an analysis of the same to be made at an early day. 



In response to the request embodied in the above communication, a 

 complete analysis has been made, the following results having been 

 obtained : 



One hundred parts of the material contain : 



Moisture 6. 38 



fOil 7.50 



I Sugar J . 50 



I Gum 2.4982 



Organic matter < Zein 1.8400> 91.4875 



Starch 65.9732 



Albuminoids 6. 1961 | 



Cellulose 5. 9800 J 



fSilica 0.1479^ 



Lime 0.0797 



I Magnesia 0. 1014 



Inorganic matter \ Peroxide of iron 0.0424 J> 2. 1319 



I Phosphoric acid 0.9698 



Potassa 0.6237 



(.Soda 0.J670J 99.9994 



