148 NATIVE BRITISH ORCHIDACEyE 



In all the above 0. purpurella is the dominant parent, the signs of G. conopsea being 

 much less evident. They are (i) longer and more slender spike, (2) smaller, paler 

 flowers, (3) longer much more slender spur. The actual diiference in length is small, 

 but the much greater slenderness gives the impression of greater length than the 

 measurement suggests. 



G. conopsea x alhtda, p. 150. G. conopsea x Anac. pjramidalis, p. 156. G. conopsea x 

 Caloglossiim viride, p. 127. 



2. Gymnadenia albida Rich. 



PI. 25 A (p. 137); PI. F, fig. I (p. 123). White Mountain Orchid, Small White Orchid 



Tubers widely divergent, long, thickened and joined at base, gradually tapering; 

 roots long, fleshy, much tliinner. Stem 10-30 cm., erect, stiff, solid, cylindrical, 

 slightly angled above, glabrous, pale green, with 2-3 brownish or whitish leafless 

 sheaths at base. Lower leaves ± 4, somewhat distant, sheathing at base, oblong- 

 ovate to oblong-lanceolate, shortly pointed, tapering at base, often broadest above 

 the middle, keeled, firm, rather thick, glossy above, with 4-6 parallel veins on each 

 side of mid-rib, and rows of very numerous short translucent dashes between the 

 nerves, densely dotted below with papillas; upper leaves 1-2, small, bract-like, acute, 

 narrow. Spike 3-6 cm., cylindrical, dense, rather one-sided. Flowers many, very 

 small, almost tubular, white and faintly scented, with hanging trifid lip. Bracts 

 slightly exceeding ovary, lanceolate, sessile, tapering, obtuse, green, glabrous, 1-3- 

 nerved, the lowest about 7 mm. long. Ovary short (± 7 nim.), slightly twisted, 

 side next to stem flat, glabrous, with three rather broad ridges. Ripe capsule 6-7 cm. 

 long. Sepals short (2-3 mm.), ovate obtuse, keeled, i-nerved, white (sometimes 

 yellowish or greenish white), loosely connivent with petals to form a more or less 

 bell-shaped or tubular flower. Petals ovate obtuse, concave, rounded out on the 

 outer side, shortly clawed, 2-nerved, hooded at apex. Lip directed forwards, white, 

 yellowish or greenish white, equalUng or exceeding the sepals, as a rule deeply 

 3-lobed, edges entire; side-lobes linear, rather acute, often as long as mid-lobe (rarely 

 reduced to a tooth on each side), more or less divergent, sometimes incurved; mid- 

 lobe tongue-shaped, rather broader and usually longer than side-lobes, rounded at 

 apex, rarely acute. Spur pendent, very short, rounded, compressed from back to 

 front, yellowish, rarely half as long as ovary, with free nectar. Column short, erect. 

 Anther broad, obtuse or with a little point, greenish white, cells nearly parallel, 

 club-shaped, their bases narrow and rather wide apart, separated by a stigmatic fold. 

 Pollinia very small, less than i mm. long, pale cream, the packets of pollen rounded, 

 relatively large, caudicles very short, affixed to the minute slightly elongated viscid 

 glands, which are not enclosed in a pouch. Stigma transverse, more or less kidney- 



