280 INTRODUCTION TO EMBRYOLOGY OF ANGIOSPERMS 



the last cell of the suspensor functions as a hypophysis and con- 

 tributes to a portion of the root tip. 



Chenopodiad Type. Chenopodium bonus-henricus (Soueges, 

 1920a) is similar to Nicotiana in having a four-celled proembryo 



Fig. 152. Development of embryo in Sherardia arvensis. (After Soueges, 1925.) 



consisting of the cells /, V, m, and ci arising by a transverse division 

 of ca and cb (Fig. 153 A-C). During the course of further develop- 

 ment I, l', and m become segmented into four cells each by the 



B 



D 



E 



G 



H 



Fig. 153. Development of embryo in Chenopodium bonus-henricus. {After Soueges, 

 1920a.) 



laying down of two vertical walls oriented at right angles to each 

 other, while ci divides transversely to form n and n' and then the 

 four cells h, k, o, and p (Fig. 153 D-H). During further develop- 



