THE GENERAL CHARACTERS OP SEEDS 



447 



Fig. 



B. 



Figure 297A 



Figure 297B 



> 



297. A. Tumbling Mustard (.Sisymbrium altissinmm). A, a group of 

 seeds indicating the usual forms ; .a, one showing the hairy appearance due 

 to the mucilage, either when wet or after drying. B, several seeds, natural 

 size. 



Hedge Mustard (.Sisymbrium officinale). A, a group of seeds showing the 

 prevailing forms ; a, one showing the fine hairlike mucilage as it appears 

 when wet or after drying. B, group showing the natural size. 

 (After Hlllman, Bull. Mich. Agr. Exp. Sta.) 



Marsh Cress {Badicitla palustris (L.) Moeneh.). 



Pod ovoid; seed pale reddish brown, oval, finely reticulated, 



length about .6 2-3 nun. ; sear near one end, occupying a deep 

 notch in the contour of the margin. 



Fig. 298. Marsh Cress (Radicula palustris). 

 (Drawing by Ada Hayden.) 



Winter Cress {Barbarea vulgaris R. Br.). 



Seed oblong, flattened, one-sixteenth in. in length ; surface finely 

 reticulated ; the scar a light-colored appendage at one end ; position 



m 









a 



Fig. 299. W^inter Cress (Barbarea vulgaris). A, various forms of seeds, 

 seed in cross section. C, seeds, natural size. 

 (After Hillman, Bull. Mich. Agr. Exp. Sta.) 



