2o8 



A TEXT-BOOK OF BOTANY. 



Tannin Idioblasts were first observed by Zopf in a number 

 of genera of the Fumariaceae (Fig. 115). These are somewhat 

 analogous to and resemble the latex or pigment cells in the Papa- 

 veraceae. They develop in the meristematic cells of certain tissue 

 systems and remain constant throughout the life of the plant. The 



Fig. 114. Inclusion Cells: A, section of leaf or Pistacia Lentiscus showing numerous 

 Inclusion cells (in) in the upper palisade layer and cells of mesophyll; calcium oxalate 

 (kr); palisade layers (pa) ; loose mesophyll (m) ; fibro vascular bundle (i); upper epidermis 

 (ep); granules of fatty substance (i); lower epidermis (ep) ; stoma (sp). B, Inclusion cells 

 or tubes (k, 1, m) in the fruit of the date palm; k, showing a homogeneous amorphous 

 content; 1 and m, separation of irregular inclusion masses in form of projections from the 

 wall. — After Hanausek. 



cells vary in shape, composition of wall, and color of contents. 

 They may be either short, isolated cells or occur in chains ; or 

 they may become elongated, resembling fibers. The walls may be 

 composed of cellulose or contain a certain amount of lignin or 

 suberin. Some of the cells may contain a nucleus. The cell-sap 



