POISONOUS AND INJURIOUS WEEDS 105 



out any injurious results. As a matter of fact, buttercups being 

 usually most plentiful in luscious pastures where plenty of 

 more appetising food is available the cattle thrust them aside 

 and do not eat sufficient to harm themselves. The degree 

 of toxicity varies with the stage of growth, as the young 

 shoots in the spring are almost harmless in most species, but 

 the amount of the poisonous substance increases as time goes 

 on, often reaching a maximum at the time of flowering, the 

 blossoms being more poisonous than other parts of the 

 plants. 



Corn cockle (Lychnis githagd}. The damage wrought 

 by this weed is very generally recognised, both with regard to 

 its effect on stock and on human beings. As so often happens 

 the reports as to its toxicity are very varied, but the consensus 

 of opinion brands corn cockle as productive of much harm. 

 The whole plant is more or less poisonous, but the seeds are 

 by far the most dangerous and most of the trouble arises 

 when they are eaten. As they are much the same size as 

 wheat grains they are difficult to separate out, and when they 

 are ground up they give the flour an unpleasant greyish colour, 

 and, if sufficiently plentiful, render the bread injurious to 

 health. The poisonous principle, githagin, is not supposed 

 to be destroyed by baking, 1 or, even if partially decomposed, 

 sufficient remains unchanged to make the bread harmful, 2 and 

 fatal results have followed the use of it. 3 



Animals vary in their response to the action of corn cockle, 

 but from the various experiments quoted by Long it is appar- 

 ent that calves, pigs, and horses are very susceptible, and that 

 on the whole young animals are more harmed than older ones. 

 It is less certain how far birds and poultry are affected, but 

 Hungarian experiments 4 have shown that geese died when fed 

 with meal containing 40 to 50 per cent, of corn cockle seeds, 

 even when this meal was added to other food. Degen also 

 states that corn cockle can produce grave symptoms of poison- 

 ing in poultry, the pathological symptoms closely resembling 

 those of acute mineral poisoning. 



The weed is sometimes plentiful in wheat crops, but as 



1 Henslow, G. (1901), loc. cit., p. 60. 



2 " Some Weeds of Iowa " (1903), Experiment Station, Iowa State College, 

 Bull. 70. 



3 Long, H. C. (1917), loc. cit., pp. 19-22. 



4 Degen, A. (1916), Kiserletitgyi Kozlemenyeh, XIX, Part I, pp. 11-21. See 

 Internal. Review of Set. and Pract. of Agric. (1916), VII, pp. 1629-1630. 



