464 



WEED FLORA OF IOWA 



Figure 326A 



Figure 326B 



Figure 3260 



Fig. 326. A. Common Morning-glory (Ipomoea purpurea). B. Small Bind- 

 weed {Convolvulus arvensis) . a, b, different faces of seed, c, cross section, 

 d, natural size. C. Wild Morning-glory (Convolvulus sepium). a, b, dif- 

 ferent faces of seed, c, natural size. 



(A, drawing by Charlotte M. King; B and C, after Hillman.) 



Wild Morning-glory (Convolvulus sepium L.). 



The outer surface rounded ; inner face with prominent ridge and 

 a depression on each side; seed one-quarter in. long; smooth, brown- 

 ish or blackish, with minute projections over the surface ; hilum 

 prominent, light brown, in semicircular depression. 



Field Dodder (Cuscuta arvensis Beyrich.). 



Capsule globose, indehiscent; seed spherical to kidney-shaped, or 

 ovate, occasionally with prominent angles ; one-twenty-fourth to 

 one-sixteenth in. long; roughened but not pitted, dull yellowish, 

 grayish or light brown ; scar at one extremity, frequently elevated 

 and prominent ; Mr. Hillman finds field dodder seeds usually lighter 

 than those of Chilean dodder; in some samples the Chilean dodder 

 seeds are the lighter in color. Appears in clover seed, in many cases 

 abundantly. 



Fig. 327. Field Dodder (Cuscuta arvensis). 

 (A, after Hillman, Bull. Nev. Agr. Exp. Sta. ; B, drawing by C. M. King.) 



