144 Transactions. 



Stomates are confined to the lower surface. The guard-cells are small, 

 with thickened walls, and the stomates are protected by guard-cell ridges. 



Below the epidermis there is a well-marked hypoclerma ; the upper 

 hypoderma consists of 1 layer of large cells with thick walls, while the lower, 

 a layer 1-2 cells thick, is composed of smaller cells, also with thick walls. 

 All the hypodermal cells contain tannin. 



The chlorenchyma is differentiated. The palisade tissue consists of 

 3 compact row^s of cells, most of which contain tannin. The spongy tissue 

 is composed of very irregular cells loosely arranged, so that there are large 

 intercellular air-spaces. These cells have thickened walls, and many of 

 them contain tannin. 



The bundle-sheath consists of small, oval, thin-walled cells which con- 

 tain tannin. Above the xylem and below the phloem there is stereome, 

 consisting of small cells with thick walls, the cells adjacent to the phloem 

 being smaller than those above the phloem. The xylem consists of wood- 

 fibres and vessels of small diameter ; these are arranged regularly in rows, 

 which are separated by rows of small, thin- walled, parenchymatous cells 

 which contain tannin. 



Stem (fig. 8). — Fig. 8 is a diagrammatic view of a young stem. 



The epidermis is comj)osed of very small thin-walled cells ; there is a 

 thick cuticle. 



The cortex consists of small thin-walled cells, more or less rounded in 

 shape, the outer layers containing small chloroj)lasts. Most of the cortical 

 cells contain tannin. 



The pericycle fibres form a continuous ring round the phloem. The 

 fibres are of small diameter, and their walls are very thick. 



All the phloem parenchyma cells contain tannin, as do also the cells 

 of the medullary rays and of the pith. The cambium is well marked, con- 

 sisting of 3 rows of small regular cells. The xylem consists of vessels of fairly 

 large diameter, and of wood-fibres of small diameter. The medullary rays 

 are uniseriate, and their cells have thickened lignified walls. 



The pith consists of rather small roundish cells which are closely arranged 

 together. Some of the pith-cells contain crystal-aggcegates of calcium 

 oxalate. 



15. Metrosideros lucida A. Rich, 



Usual Growth-form. — " Usually a tall erect branching tree 30-60 ft. high, 

 but often dwarfed to a small bush in subalpine or exposed localities ; bark 

 pale, papery ; branchlets and young leaves silky. Leaves l|-3 in. long, 

 elliptic-lanceolate or lanceolate, acuminate, very coriaceous, pale glossy- 

 green above, dotted with oil-glands beneath, narrowed into a short stout 

 petiole." 



Mineral Belt Growth-form.. — A small, rounded, woody bush, with leaves 

 f-l| in. long. 



Anatomy. 



The structure of both stem and leaf corresponds with that in M. robnsta 



16. Epilobium pedunculare Hook. f. 



Growth-form. — A small herb, with slender prostrate branches 2-6 in. long, 

 which root at the nodes and are sparingly branched. The branches are 

 almost glabrous. The leaves are opposite, -|— |^ in. long, orbicular-ovate, 

 rounded at the apex, fleshy and entire, and with a very short petiole. 



