362 
Orchidacese. 
540. Acorus. Sweet-flag. VI, 30. 
1. Lsensiform. Spadices apparently lateral.—Marshy places; 
water-side; scattered (wanting in G.? S.). 6 
Calamus L. 2070. 
112. Orchidaceae. 
541. Orchis. Orchis. XX, 6. 
1. Lip undivided ....... 2 
— Lip 3-toothed, S-fid or 3-partite . ... 3 
2. Tubers palmate. FIs blackish red. Comp, the genus 
Nigritella. 
— Tubers undiv. FIs white. Comp, the genus Platanthera. 
3. Lip 3—4 times as long as the other divisions of the 
perianth; the middle lobe 45—60mm long! Comp, the 
genus Himanthoglossum. 
— Lip shorter, or at all events not 3—4 times as long as 
the divisions of the perianth .... 4 
4. The 5 divisions of the perianth all converging in the 
form of an helmet (converging feebly in 2076) . 3 
— The 2 lateral, of the outer divisions of the perianth 
spreading or reflexed ...... 13 
5. Tubers div., palmate. FIs greenish or whitish. Comp, 
the genus Coeloglossum. 
— Tubers undiv. FIs of a different colour . . 6 
6. Lip 3-partite, the middle lobe 2-fid or 2-lobed, gen. with 
a small tooth in the incision. Stem with reduced, sheath¬ 
like Is above ........ 7 
— Lip 3-fid or 3-lobed, the middle lobe undiv., or at most 
emarginate. Stem almost entirely leafy . . 11 
7. Bracts, at most, 1 /4 the length of tho ovary. Type of 
O. miliiaris ........ S 
— Bracts, at least, half as long as the ovary . . 10 
8. Helmet shortly ovoid, blackish red outside (darker 
than the lip). Bracts V 5 — x ji the length of the ovary. 
Middle lobe of the lip with a base 4—5 times as broad 
as the lateral lobes. O. fusca Jacq.—Thickety hills, wood- 
sides; not common (wanting in G. T. W. U.). 5 
purpurea Huds. 2071. 
— Helmet ovoid-lanceolate, rosy gray (lighter than the lip). 
Bracts V 4 —V 5 the length of the ovary. Middle lobe of 
the lip almost as narrow as the lateral lobes . .9 
9. Lobules of the middle lobe as narrow as the lateral 
lobes of the lip, elongated and bent upwards. FIs of 
the spike opening from the top downwards, while in 
