286 INTRODUCTION TO EMBRYOLOGY OF ANGIOSPERMS 



tiers, I gives rise to the cotyledonary region, V to the hypocotyle- 

 donary region, h to the initials of the root periblem, and h' to the 

 root cap (Fig. 1WG-K). 



Comparing the development of the embryo of Drosera with the 

 types previously described, it is clear that the filamentous form of 

 the proembryo corresponds with that in the Solanad type (Fig. 150) ; 

 the behavior of the tiers h and h' corresponds with that of the tiers 

 m and n in the Asterad type (Fig. 148) ; and the disposition of the 



Fig. 160. Development of embryo in Drosera rotundifolia. (After Soneges, 1986c.) 



quadrants resembles that under the Solanad and Chenopodiad 

 types (Fig. 153). However, the greatest resemblance is with the 

 Caryophyllad type (Fig. 156) as in both cases the embryo is pro- 

 duced almost entirely from the terminal cell of the proembryonal 

 quartet, while the basal cell cb of the two -celled stage takes practi- 

 cally no part in further development. 



MONOCOTYLEDONS 



As already mentioned there is no essential difference between the 

 monocotyledons and the dicotyledons regarding the early cell divi- 

 sions of the proembryo. However, since the mature embryo is so 



