Corn cockle

The latter indicate corn-cockle, vetch, ergot or mites coloured spots— usually red, violet or blue—justify suspicion of the presence of darnel, lathyrus, melampyrum, or other seeds the perisperms of which contain special pigments reacting with Vogl s add solution. 

Microscopic examination. Flour should not contain substances extraneous to wheat or injurious seeds (darnel, corn-cockle, mclampyrum, ergot, etc.). 

Common Names Cockle, Corn Cockle, Com Rose, Crown-Of-The-Field, Purple Cockle... 

Goering, K. Fritts, D. H., and Allen, G. D. (1974). A comparison of loss of birefringence with the percent gelatinization and viscosity on potato, wheat, rice, corn, cow cockle, and several barley starches. Cereal Chem. 51, 764-771. 

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