Fig. 73. Grass Embryos 



A, Triticum vulgare. Embryo in longitudinal median section; sc, scutellum, with 

 its vascular trace, r/; c, coleoptile; /, /g, first and second plumular leaves ; i, shoot 

 apex, with third leaf; b, coleoptile axillary bud primordium; e, epiblast; /, first 

 internode; h, first node; co/, coleorhiza ; r, root, with root-cap, /r; 5h, remains of 

 suspensor ( x 53, after McCall). B, C, Paspahun dilatation. B, Young embryo, 

 showing the considerable enlargement of the posterior side. C, Older embryo, show- 

 ing the scutellum, coleoptile primordium, shoot apex and first root (after Bennett). 

 D, Avena sativa. Fully developed embryo. The scutellum has a small ventral scale 

 (on right); the other details are as in A (after Avery). 



