Fig. 50. Toneya mtcifera and T. taxi folia 

 A, Proembryo with two nuclei ( X 165). B, Four-celled proembryo ( x 180). C-E, 

 Older proembryos, with ten to eighteen cells, and showing the beginning of elonga- 

 tion in the cells of the suspensor (C, X 180; D, E, X 165; after Buchholz). F-L, 

 Torreva taxifolia. F, Fertilisation; the male and female nuclei are m contact, the 

 cytoplasm of the male cell being closely applied to the egg nucleus ; the cavity in the 

 egg cytoplasm is caused by the inrush of the pollen-tube contents ; the non-functional 

 male cells, and the tube and stalk nuclei, are seen above. G, Two-celled pro- 

 embryo. H, Four-celled proembryo, with beginning of wall formation. J, Pro- 

 embryo shortly after partition walls have been laid down; the proembryo passes the 

 winter in this state. K, Cross-section through the suspensor cells. L, Proembryo 

 showing the elongation of the suspensor cells on the renewal of growth in Spring 

 (F-L, X 150; after Coulter and Land). 



