442 REPORT UNITED STATES ENTOMOLOGICAL COMMISSION. 



with whom we bad arranged to make an analysis. The following is 



Professor Kedzie's report : 



Kansas State Agricultural College, 

 Chemical Department, Noveruhei fi, 1&77. 

 Dear Sir : In the early part of the month of August last I received from Mr. Emmet 

 F. Hill, of Spirit Lake, Dickinson County, Iowa, a two-quart bottle filled with the ex- 

 pressed juice of the Rocky Mountain locust {Cdloptenus spretus), and at the same time 

 received your letter of August 2, requesting me to make such examination of the pro- 

 duct as should be found possible. In a minute account, forwarded me soon after, Mr. 

 Hill states that the bottle of extract sent me was a portion of seven pints of juice ob- 

 tained from three-eighths of a bushel of the locusts, weighing altogether 25 poun(}s, by 

 prolonged pressure under an ordinary screw-and-lever cheese-press. The bottle of ex- 

 pressed juice placed in my possession I found upon examination to contain also a con- 

 siderable quantity of macerated tissue of the locusts, giving the liquid a somewhat 

 viscid character and dark brown-color. Decomposition had so far progressed as to 

 render very rapid work necessary in order to carry out the programme for the investi- 

 gation which I had proposed. The liquid was markedly alkaline in reaction. Its 



proximate composition I determined as follows : 



Per cent. 



Water , 87.083 



Oil '. 004 



Solid organic matter 12. 903 



Mineral matter (ash) .010 



100.000 



The oil referred to above was obtained by prolonged digestion with sulphuric ether. 

 It is a fine, transparent, reddish-brown oil of very pungent and penetrating odor ; and, 

 although probably of little practical importance, is of great interest, considering its 

 origin and properties. I. have still to determine its ultimate composition, and for con- 

 venience in future reference I will venture to designate it calopiine. The ultimate 



constitution of the ash of this locust-extract I determined as follows : 



Per cent. 



Silica M. ....... 12.100 



Sulphuric acid 1. 153 



Chlorine 1.760 



Phosphoric acid 50.713 



Lime 13.260 



Magnesia 8.511 



Potassa 7.420 



Soda 5.083 



Copper (distinct trace). 



The large proportion of phosphates which the above analysis shows in this ash would 

 not be unexpected, considering the nature and voracious habits of this insect. The 

 presence of copper in perceptible traces is also a very interesting feature of the analysis 

 when considered in connection with the fact that this metal has also been discovered 

 in the blood of other animals, particularly of the Limulus polypliemus, the ash of 

 whose blood always furnishes a trace of copper.^^ The accidental occurrence of this 

 metal in the present case is entirely precluded by the fact that in the process of care- 

 fully expressing the liquid, it came in contact with no metallic surface whatever ; 

 possibly excepting the contact of a small portion with the thread of the iron press-screw. 

 Perhaps the most interesting result of this examination, however, was that obtained by 

 the distillation of this locust-ex ract with strong sulphuric acid. In this experiment 

 150 cubic centimeters of the decomposing liquid with 75 cubic centimeters of sulphuric 

 acid were distilled at a high temperature, and the product collected through a Liebig's 



^ See Watt's Chemical Dictionary, vol. i, p. 610. 



