THALAMIFLORiE 97 



organs being close together, so that insects have to 

 come in contact with anthers and stigma to get at the 

 honey, touching the former on one side, the latter on 

 the other. The anthers and stigma frequently ripen 

 at different periods. But self-pollination often 

 occurs in the flowers of this group, many being mari- 

 time plants. 



The seeds are largely wind- dispersed in the case 

 of the plants with dehiscent pods. 



Variation in the character of the pods and the 

 relation of the radicle to the cotyledons constitutes 

 an important factor in classification. 



The Cabbages and Cresses are important econo- 

 mically, and it is from this group that a large pro- 

 portion of our vegetables and plants yielding 

 condiments, as well as potherbs and salads, are 

 derived. 



Treacle Mustard {Eryshmim cheiranthoides). 



Unlike most Cruciferous flowers, except the 

 cabbage and allies, those of Wormseed are not white, 

 but yellow, like those of the Wallflower (hence 

 cheiranthoides) . 



Supposed to be wild in the Fens, this plant is 

 found only in England and Ireland, where it is rare. 

 The usual habitat is cultivated ground, waste places. 

 I have found it most frequently on the outskirts of 

 market-gardens, allotments, and gardens, and it 

 seems to be on the increase. North of the Midlands 



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