104 



GROUND FEEDS. 



impunity. This is also true of seeds like Wormseed Mus- 

 tard, small quantities of which have proved fatal to pigs. 

 Certain other animals are similarly immune. One farmer 

 tells of a flock of geese which he fed on mill screenings 

 containing a large percentage of Frenchweed seeds. The 

 geese became very fat, and presented such a fine appear- 

 ance that he planned to present a number of them to 

 friends at Christmas. On preparing one of them for the 

 table, however, it was found that the flavour of French- 

 weed was so strong as to render the flesh unfit for food. 







Fig. 24. Seeds of Field Penny cress Thlaspi arvense. Five timea 



natural size. 



Needless to say the original plan for the disposition of the 

 flock was altered. 



The plant, which is another introduction from Europe, 

 has spread to the prairies, where it is a troublesome weed. 

 It is an erect, smooth, light green plant. The 

 radicle leaves are petioled and lance-shaped, 

 while those on the stem are spear-shaped, 

 with coarse teeth and a sagittate base. The clear whit-' 

 flowers are one-eighth of an inch in diameter and open, as 

 in other mustards, in a flat cluster at the end of an elong- 

 ating raceme. The flat seed pods are very characteristic. 



The Plant 

 and Seeds 



