ADULTERATION OF INSECT POWDER. 
(PL II, fig. 1). Durrani (.10) found difficulty in detecting daisy in 
genuine insect powder, and Beringer (2) could detect no difference 
microscopically between; the two powders. 
However easily the hairs Sehrenk has referred to may be detected 
on the unground involucral scales, their presence is very difficult to 
establish when the scales are powdered. Apparently the hairs are 
very fragile and become readily broken up in the process of grinding. 
The achenes of Chrysanthemum cineraria? folium and Chrysanthe- 
mum Leucanthemum are strikingly different in the powdered form. The 
achene tissues of the Dalmatian flowers (C. cinerariwfolhim) are char- 
acterized by the numerous crystals, which exhibit a variety of colors 
under polarized light. On the other hand, the achene tissues of the 
daisy flowers (C. Leueaiitliemum) exhibit no such crystals, but con- 
tain a notable amount of a brownish-red material, the location of 
which is readily demonstrated in a cross-section of the fruit. In 
a cross-section of the achene, crescent-shaped structures, correspond- 
ing to each of the ten ribs, stand out very distinctly (fig. 1). 
When the daisy flower heads are powdered, this brownish-red ma- 
terial contained in the crescent-shaped structures breaks up into ir- 
regular, angular fragments, sometimes attached to the surrounding 
tissues, and sometimes separated from them. These fragments assume 
a deep, brownish-red color when the powder is heated in a solution 
of chloral hydrate in water about 1:1. 
Aside from this dark brown material, a portion of the tissue from 
the white ribs of the daisy achene is another diagnostic character. 
The outer portion of the 
rib consists, in radial sec- 
tion, of what are apparent- 
ly epidermal cells. They 
appear to have a palisade- 
like arrangement, consist- 
ing of narrow, thick-walled 
cells packed very closely 
together (PL II, fig. 2). 
This tissue, which invaria- 
bly occurs in the daisy 
powder in the form of ra- 
dial sections, serves as an- 
other means for detecting 
its presence in genuine in- 
sect powder. 
Experience gained in 
the comparative study of 
a large number of samples 
ground from insect flow- 
Fig. 1. 
-Cross-section of daisy achene (illustrating crescent- 
shaped structures) . 
