438 WEED FLORA OF IOWA 



Cowherb {Saponaria vaccaria h.) . 



Seed nearly spherical, one-twelfth in. in length, minutely tu- 

 bercled; color black; immature seeds reddish; scar whitish, in de- 

 pression. Occurs in wheat and in red clover. 



Fig. 281. Cowherb (Saponaria vaccaria). A, different views of the seeds; 

 the one at the left and the lower one show the scar ; the light spots show 

 the minute surface-projections. B and C, parts of a broken seed, B re- 

 taining a part of the embryo. D, a sectional view of a seed. E, seeds, nat- 

 ural size. 



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



PORTULACACBAE, PURSLANE FAMILY. 



Purslane (Portulaca oleracea h.) . 



Seeds broadly ovate, inclined to kidney-shaped, flattened, one- 

 thirtieth in. in length, roughened by minute tubercles in concentric 

 rows: small scar at smaller end, whitish. 



Fig. 282. Purslane (.Portulaca oleracea). A, a side view of a seed, enlarged, 

 showing the whitish scar ; B, a group, natural size ; C, section of a. seed, 

 taken parallel with the faces. 



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



RANUNCULACEAE, CROWFOOT FAMILY. 



Meadow Rue (Thalictrum dasycarpum Fisch. and Lall.). 



Fruit an achene, ovoid, one-fifth in. in length, with remnant of 

 curved style, prominently ribbed, with from 6-8 wings, short- 

 stalked, glabrous or pubescent ; seed elongated, ovoid, one-tenth in. 

 long, brownish, smooth, with prominent veins near base of seed. 

 Ocoasionally found in clover seed. 



