Species of the New Zealand Orchidaceae. T43 
together. There are often six groups of xylem and phloem, the former being 
proportionately the better developed and consisting almost wholly of spiral 
tracheides. In the centre of the cylinder the cells have thin, slightly 
cutinized walls. 
In the stem the epidermis and cortex are thin-walled. The latter, 
which is not usually more than eight cells deep, consists of large elements 
containing raphides, separated by small cells with protoplasmic contents. 
Spirally marked water-storage cells occur infrequently. The vascular 
bundles are numerous and the fibres of their sheaths large. Of the latter 
there are usually two or more rows near the phloem and one near the 
xylem. Spiral tracheides are of general occurrence, but reticulate and 
regularly pitted tracheides are also to be seen. 
The pseudo-bulb is taller, more pointed at the apex, and contains more 
vascular bundles than that of B. pygmaeum . The regular, slightly elongated 
cells of the epidermis are protected by a heavy cuticle. The general tissue 
consists of large spirally marked water-storage cells and small assimilatory 
cells with numerous chlorophyll granules. Near the periphery of the 
pseudo-bulb one green cell lies at the angle of juncture of several storage 
cells, but near the vascular bundles and in the central region several 
green cells may occur together, and the large elements be segregated in 
groups of two or three. In longitudinal section assimilatory cells usually 
surround each storage cell. In the apical portion of the pseudo-bulb 
the small cells near the surface contain instead of chlorophyll a purple 
pigment in solution in the cell sap. The vascular strands are weak. A few 
slightly thickened elements occasionally adjoin the phloem. 
The leaf is broader, but proportionately thinner than that of B. pyg- 
maeum. Five large and ten smaller bundles traverse its length. The cells 
of the upper epidermis are extremely large. No papillae are present, but 
small sunken cells occur at somewhat rare intervals on the upper surface. 
Below the epidermis are two or three rows of cells with slight contents. 
Between the vascular strands the assimilatory cells are much elongated 
in the plane parallel to the leaf surface. Below these again lie more or less 
round cells connected together by tubular extensions. Large air chambers 
occur between the small stomata and the assimilatory tissue, and cells contain- 
ing raphides are present between the outer vascular bundles. One epidermal 
cell at the extreme edge of the leaf is extended into a short projection, with 
the result that the leaf margin is sharp. 
Sarcochilus ad versus, Hook. f. FI. Nov. Zel. i. 241. 
Roots numerous, long, wiry, terete. Stems short, 1-3 in. long, con- 
cealed by the imbricated sheathing bases of the leaves. Leaves few, 
distichous, spreading, i- 2 \ in. long, §-f in. broad, linear-oblong to elliptic- 
oblong, obtuse or sub-acute, jointed above the sheathing base, thick and 
