ON THE ANATOMY OP MAUNOLIACE^. ]^2l 



xyJem contains traclieae, übres, and wood-parenchyma. I)ordered pits 

 are found in the walls of the vessels ; they ap[)ear in ;i surface view 

 like a slit encircled by a halo, and not like an encircled spot as 

 commonly seen in the wood of Fitnis. Most of the medullary rays 

 consist of single rows of cells. 



The parenchymatous cells of the pith have thick lignified walls, 

 even in the young specimen, and contain an ample quantity of starch. 



Petiole. — The epidermis consists of a single layer of cells, and the 

 cuticle is not well developed. The hypoderma is represented by a 

 layer of thick-walled parenchymatous cells. There is present in the 

 extei-nal cortex no sclerenchymatous element, but deeper in this region 

 there lies a zone of tissue presenting an irregular appearance, due 

 to the distortion of parencliymatous cells (IM. II, Fig. (), a). The 

 fibro-vascular bundles are arranged in a circle, as in the stem, and 

 enclose the pith in the centre (PI. II, Fig. (!). The bundles are encir- 

 cled by a well-developed sclerenchymatous sheath, which is inter- 

 rupted by parenchymatous ceils only at a few points (PI. If, b'ig. (i). 

 The filjres are unlignified in the basal portion of the petiole. 

 Prismatic crystals are found in the phloem. The pith parenchvma 

 unlike tlraf of the stem has unlignified walls. 



Blade. — Its general structure, as also the form of its stomata, 

 has no iK'Culiaritv. There are se\eral main-ribs instead of a sin^de 

 midril). and their hljnj-vascular bundles jti'esent a semi-circular 

 arrangement, while tinsse of the petiole ai-e circularly arranged. A 

 grouj) of thick- walled cells is found within that poi-ti(jn of the 

 epidermis, which lies on the u])pei' side of the main-ribs. Aggregates 

 of crystaJs are found in the cortical region of the main rib. The 

 CLiticidar ridges ar(3 not so conspicuous as in the midrib ol hliiplehva. 



liooi. — The structure of the older I'oot is similar to that (jf the 

 stem. Crystals are copiously found here also in the phloem. 



