214 MR. P. GROOM—CONTRIBUTIONS TO THE 
EXPLANATION OF THE PLATES. 
Abbreviations. 
cx.=cortex. endo.—endodermis. ep.=epidermis. w.ep.—epidermis of the 
upper face of a leaf. /.ep.= epidermis of the lower face of a leaf. ex.=exodermis. 
m. = mucilage-cell. mé.p. = multicellular protuberance. 2.= mycorhizal 
hyphe. my.m.= mycelial mass. my.p.= mycelial pegs. pc.=pericycle. 
pil-piliferous layer. pl.=placenta. ph.=phloém. p.ph.=protophloém. 
ph.s.—sieve-tube. ph.s.c.=callus on sieve-plate. ps.=passage-cell. r.m.= 
raphide-mucilage cell. sc.—sclerenchyma. sh.=sheath. g.sk.=general sheath. 
b.sh.—sheath round one bundle. sp.=spiral vessel. sw./.=outermost layer 
of cortex with suberized walls. ¢r.=tracheide. a«y.=xylem. 2xy.an.=annular 
vessel. 
Prate IV. 
Fig. 1. Galeola javanica. Transverse section of root, near the base, showing 
the outer layers, (Leitz 1. 7, reduced to z.) 
2. Ditto. Transverse section of root, showing a single layer of scleren- 
chyma lying outside the endodermis and interrupted by passage- 
cells opposite the xylem ; also shows two bundles of phloém. (Leitz 
1. 7, reduced to 4.) 
3. Ditto. Transverse section of a vascular bundle and part of the general 
sheath of the scape. (Zeiss 3. D, reduced to 4.) 
4. Ditto. Transverse section of part of a bract. (Zeiss 3. A.) 
5. Ditto. Transverse section of part of a subterranean scale. (Zeiss 
3. A.) 
6. Ditto. Transverse section of part of placenta showing two mucilage- 
cells and portion of a third, also parenchyma devoid of starch. 
(Zeiss 1. D, reduced to 4.) 
Pare V. 
Fig. 1. Aphyllorchis pallida. Transverse section of part of root, showing one 
bundle of xylem and two of phlo&m. (Zeiss Apo. 8 mm., Comp. Oc. 8, 
reduced to 4.) 
2. Ditto. Transverse section of vascular bundle of scape. (Zeiss 3. D, 
reduced to $.) 
3 a, b, c, d. Ditto. Surface-view of stomata of leaf. (Zeiss 3. D.) 
4. Ditto. Transverse section of ovary-wall. Dots represent starch. 
(Zeiss 1. A.) 
5. Lecanorchis malaccensis. Longitudinal section of outer portion of root. 
(Zeiss Apo. 8 mm., Comp. Oe. 8, reduced to 3.) 
6. Ditto. Transverse section of stele of root. (Zeiss Apo. 8 mm., Comp. 
Oc. 4, reduced to 1.) 
7. Ditto. Transverse section of an incompletely collateral bundle from 
base of scape. The arrow points radially outwards. (Zeiss 3. D, 
reduced to 4.) 
