ON THE ADULTERATION OF COCHINEAL. 57 
ART. XVII.— ON THE ADULTERATION OF COCHINEAL. 
BY M. LETELLIER, OF ROUEN. 
Two varieties of cochineal are found in commerce, the 
gray and the black. No satisfactory explanation has hith- 
erto been given of this difference. Some think that it is 
owing to the different methods employed of killing the in- 
sect, others attribute it to a different mode of cultivation. 
MM. Fee, in his ' Cours d'Histoire Naturelle Pharmaceu- 
tique,' Btissy, in his « Traite des Falsifications des Drogues 
simples/ and Boutron Charlard, in a note inserted in the 
6 Journal de Pharmacie/ vol. ii. tenth year, are of the same 
opinion ; they think that these kinds of cochineal are only 
one and the same species, and the differences which are 
observed in them are owing to the custom of plunging the 
black cochineal into boiling water in order to kill it, which 
deprives it of the whitish powder with which it is naturally 
covered. The gray cochineal, on the contrary, which is 
killed by being exposed to the heat of an oven, preserves 
its proper color. M. Guibourt, contrary to these gentle- 
men, thinks that black cochineal is a variety produced by 
cultivation, and still further removed from the savage state 
than the gray cochineal. Black cochineal is, according to 
this gentleman, richer in coloring matter and held in higher 
estimation. In confirmation of what he advances, he states 
that at Bordeaux persons are employed in converting, by a 
peculiar process, gray cochineal into black, at an expense 
of fifty centimes (five pence) per pound ; he also agrees 
with M. Bussy, that if at the present time talc or white 
lead is added to cochineal, it is not black cochineal which 
undergoes this adulteration, but gray cochineal, with the 
sole view of increasing its weight. According to M. Fee, 
gray cochineal is generally more esteemed than black, be- 
cause this latter has lost a little of its coloring principle by 
