532 



WEED FLORA OF IOWA 



Fig, 409. Black Bindweed. Surface view of the pericarp from below. 

 Significance of letters same as In Fig. 406. 

 (After "Wlnton, Conn. Agr. Exp. Sta.) 



X 160. 



CHBNOPODIACEAE, GOOSEFOOT FAMILY. 



Groosefoot or Lamb's Quarters (Chenopodium album L.). 



Harz has given an account of the structure of Beta and Spinaciw. 

 The structure of the seed of lamb 's quarters is somewhat different. 

 The thin utricle consists of an epidermal layer of somewhat wavy 

 cells and an indistinct layer underneath. The testa contains the 

 brownish pigment. The cells are thick-walled ; the nucellus is com- 

 pressed. The cells of the endosperm are large and contain an 

 abundance of small starch grains. 



Russian Thistle (Salsola kali (L.) var. tenuifoUa G. "W. F. Meyer) . 



The seed is without endosperm; the embryo fills the seed, and 

 is coiled in a conical spiral. The seed coat consists of two parts, 

 a layer of three rows of elongated cells followed by a layer of 

 three rows of irregular parenchyma cells. One side of the seed 

 coat is wider than the other and these cells contain an abundance 

 of calcium oxalate crystals. The cells of the outer layer of the 



