STRUCTURE OF FOSSIL PLANTS 



55 



Ground Tissue 



Parenchyma. — Simple soft cells, 

 either closely packed, as in 

 fig. 24, or with air spaces 

 between them. Compare 

 78, B, for fossil. 



Palisade. — Elongated, closely 

 packed cells, p, chiefly in 

 leaves, lying below the epi- 

 dermis, e, fig. 25. Com- 

 pare fig. 34, /, for fossil 

 palisade. 



Fig. 25 



Endodermis. — Cells with 

 specially thickened walls, 

 en, lying as sheath be- 

 tween the parenchyma, 

 c, of ground tissue, and 

 the vascular tissue, s, fig. 

 26. Compare fig. 108 

 for fossil endodermis. 



en 



Fig. 26 



Latex cells. — Large, often much 

 elongated cells, m, lying in 

 the parenchyma, /, fig. 27, 

 which are packed with con- 

 tents. Compare fig. 107, s. 



Fig. 27 



