THE GENERAL CHARACTERS OF SEEDS 



431 



t 



m 



Fig. 266. Pennsylvania Smartweed {Polygonum pennsylvanicum) . A, a side 

 view of a seed (achene). B, one surrounded by the calyx; the opposite side 

 has two segments between those on the edges. C, a cross section of a 

 seed. D, seeds, natural size. 



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



Bushy Kno tweed (Polygonum ramosissimum Mx.). 



Achenes sharply 3-angled, sides less deeply concave than in 

 P. aviculare, one-eighth in. in length; color blackish, dull; calyx 

 greenish, light straw-colored in dried specimens. 



Figure 267 A 



Figure 2670 



Figure 267C 



Figure 267B 



Fig. 267. A. Pennsylvania Smartweed {Polygonum pennsylvanicum) . B. Tan- 

 weed {Polygonum muhlenbergii). C. Bushy Knotweed {Polygonum ramos- 

 issimum). 



(A and B, drawings by Charlotte M. King; C, drawings by L. R. Collins.) 



CHENOPODIACEAE, GOOSEFOOT FAMILY. 



Cycloloma (Cycloloma. atriplicifolium (Spreng.) Court). 



Fruit enclosed by the calyx, lower surface prominently rayed, 

 upper surface depressed, wing-margined, one-tenth to one-eighth in. 

 in diameter; seed nearly spherical, somewhat flattened, one-twelfth 

 in. in diameter, blackish ; scar whitish ; embryo slender, forming a 

 ring about the endosperm. 



Fig. 268. Cycloloma {Cycloloma atriplicifolium). a, b, seed in envelope; c, 



d, enlarged views ; e, seeds, natural size ; f, cross section. 



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



