440 



WEED FLORA OF IOWA 



Small-flowered Crowfoot (Ranunculus abortivus L.). 



Achene flattened-cireular, with 2 convex faces, orange-brown in 

 color, smooth and shining', very slightly impressed with wrinkles; 

 remnant of style present as a short curved point on margin. 



a 



/ 



~*\ 



% h 



J#. 



a 



Figure 2S5A Figure L K ">B 



Fig. 285. A. Small-flowered Crowfoot (Ranunculus abortivus). a, 



enlarged ; b, end view ; c, achenes natural size. 

 B. Tall Buttercup (Ranunculus acris). a, b. different views of seed 

 section ; d, natural size. 



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



achenes 

 c, cross 



Tall Buttercup (Ranunculus acris). 



Carpel 1-ovuled; achene flattened, tipped by remnant of curved 

 style, one-tenth to one-eighth in. long; color greenish to brownish; 

 surface apparently smooth, minutely pitted; scar minute, in a 

 whitish depression at base of achene. 



PAPAVERACEAE, POPPY FAMILY. 



Poppy (Papauer somniferum L.). 



Seed about 1 mm. in length, kidney-shaped, one end being slightly 

 larger than the other; hilum and chalaza in a notch, connected by 

 a short raphe ; surface covered with fine, beautiful reticulations ; 

 embryo straight ; considerable endosperm. 



**4§g§ 



Figure 2S6A 



Fig. 2S6. A. Poppy (Papaver somniferum) 

 B. Prickly Poppy (Argemone intermedia) . 



(A, after Winton. B, drawing. C. M. Kin 



Figure 2S6B 

 To the left embryo of seed. 



.) 



