236 PLANT ANATOMY. 
in which the processes of development are actively effected. 
While the cells of the epidermis, of the cambiform, of the cam- 
{ Fig. 151.—Moniliform tissue from Rhizoma Calami, Transverse section through the 
nucleus-sheath; 0, oil-cells. 
bium, and of the medullary rays are closely united to each other, 
without intervening spaces—the wood, the bark, and the tissue 
Fic. 152.—Transverse section from the sarcocarp of Fructus Aurantiorum; the 
large, branched cells having sieve-like pores at their points of connection, for example, 
at cr; q, branches of cells cut transversely; 5, imperfectly developed, large crystals of 
oxalate. The dotted places represent the air-cavities; v, fibro-vascular bundle. 
of the leaf possess an abundance of such, mostly triangular or 
quadrangular, intercellular cavities. Aquatic plants, especially 
