THE EEST-HAKBOW. 



Onoiiis arvensis. Nat. Ord., Legum'mosa. 



HE rest-harrow, like the bush -vetch, 

 the subject of a previous illus- 

 tration, is one of the numerous 

 examples that may be met with of 

 what are termed botanically papi- 

 lionaceous flowers. The term is de- 

 rived from the Latin word papilio, 

 a butterfly, since the blossoms of 

 all these plants have an upright 

 and often gaily-coloured petal at 

 the upper portion of each flower 

 that to some people, at least, appears to 

 have suggested one of these insects, 

 ^ though probably most of our readers will 

 only see in this a very considerable 

 stretch of the imagination. The order to 

 which the rest-harrow belongs is a very 

 natural one, as the plants composing it 

 possess several marked characteristics in common that unite 

 them to each other and sever them from other flowers. 

 All the British species have flowers of the butterfly type, 

 and in these the sepals are always so united as to form 

 a calyx that seems like a deep cup; from this springs 

 the corolla, very irregular in form, and consisting of five 

 petals. The upper one of these in the expanded flower, 

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