52 NATIVE BRITISH ORCHIDACEiE 



its high estate, assuming that it is really the case that it is entirely self-fertilised". 

 Now that I have witnessed the visits of insects to ensiJoUa, rubra, and also grandiflora, 

 I no longer believe there has been any degeneration in Cepbalaiithera, but that it 

 presents a case of persistence to the present day of an extremely ancient method of 

 cross-pollination, which possibly prevailed in the Orchidaceas before a rostellum had 

 been evolved in that family. The absence of a rostellum and the single pollen-grains 

 are signs not of degeneration, but of a very early phase of evolution.' 



2. CePHALANTHERA ENSIFOLIA Richard 



PI. 4; PL C, fig. 2 (p. 50). Sword-leaved Hellehorine 



Rhizome knotted, with stiff wiry roots. Stem 20-50 cm., leafy throughout, pale 

 green, slightly ridged above through decurrence of edges of bracts, with short inter- 

 nodes (1-2 cm.), and 2-4 whitish or green-tipped sheaths at base. Leaves alternate, 

 mostly in two opposite ranks, obliquely erect or horizontally spreading, often folded, 

 long (7-10 cm.), narrow (± 1-5 cm.), oblong, tapering, stiff, acute, glabrous, with 

 3-5" prominent and numerous fainter nerves; lowest leaves shorter, obtuse, upper 

 linear, very narrow, acute, sometimes exceeding the spike. Spike lax. Flowers 3-15 

 or more, pure white, obliquely erect, smaller and opening wider than those of 

 C. grandiflora. Bracts triangular, acute, i-nerved, very short, but the lower one or 

 two sometimes up to 8 cm. long, linear, acute, very narrow, with 3-5 principal and 

 some intermediate nerves. Ovary 1-1-5 cm. long, sessile, cylindrical, slender, 

 glabrous, twisted, 6-ridged, Sepals lanceolate, keeled, acute, faintly 1-5 -nerved, 

 I-I-5 cm. long. Petals shorter and broader, oval, obtuse, 3-5-nerved. Lip shorter 

 than sepals, jointed ; basal half somewhat sack-shaped with two rounded ears embracing 

 the column (making the flower tubular), white with an orange blotch at base, front 

 half (epichile) somewhat heart-shaped, broader than long, curved, trough-hke, wliite, 

 with 3-5 orange-yellow, parallel crests and turned down, rounded orange tip, covered 

 with dense papilla. Column long, erect, flat in front, rounded beliind, with a nib-like 

 filament at the back from the tip of wliich the anther is suspended below the middle 

 of its back. Anther whitish, ovoid, rounded, flat in front, tilted forward and 

 firmly pressed against the back of the stigma, with an obtuse white staminode (rudi- 

 mentary anther) on each side at the base, tending to keep it in position. Pollinia 

 two, long, curved, yellowish white, sometimes split in two, or nearly so, their convex 

 centres projecting slightly from the cells of the anther, where they remain till removed 

 by insects. Stigma on the front of the column just below the anther, transversely 



' Journ. Linn. Soc. Bot. xlv, 511 (March, 1922). 



