159. ORCHID ACE.E. 



[1. Habenaria. 



1. HABENARIA, WilU. 



Terrestrial tuberous herbs with 2-niany leaves with sheathing 

 bases. FloAvers large or mod. -sized, more rarely small, white, green 

 or yellow. Lateral sepals mostly spreading or reflexed, dorsal some- 

 times connate with the petals. Petals simple to 2-partite with often 

 filiform segments. Lip various, usually 3-lobed, always spurred at 

 the base. Column short with usually small erect 3-lobed rostellum, 

 midlobe often minute between the cells of the anther or 0. Anther 

 erect adnate to the column Avith cells parallel or divergent below and 

 their bases often produced into long or short grooves or tubes in which 

 the caudicles of the pollinia lie ; pollinia granular with short or 

 elongate basal caudicles and an exposed gland. Stigma 2-lobed or 

 2 more or less developed papillose often clavate processes. 



(In U. Susannce the stigma is a single viscid area, and on this account it is some- 

 times inchuled in a separate genus, Platanthera, Rich. The last foui- species are 

 sometimes placed in a separate genus, Peristylus.) 

 I. Flowers • 5" diam. or over with lateral sepals free spread- 

 ing reflexed or deflexed. Spur elongate (Spp. 1-14) : — 



A. Petals 2-fid or 2-partite. Lip 3-partite. Stem leafy 



from base upwards : — 

 Sepals with filiform tips . , . . .1. stenopetala. 



Sepals acute ...... .2. digitata. 



B. Petals entire (Spp. 3-14) :— 



1. Lip 3-lobed or -partite (Spp. 3-13) 



Imately lacerate or pec- 



Side-lobes of lip 



tinate : — 

 Stem tall leafy with large white flowers 



b. Side-lobes of Up entire or only slightly 



toothed, broad {cp. c). Fls. white (Spp. 

 4-8) :— 

 i. Leaves appressed to the ground : — ■ 



t Lip not or hardly longer than lateral 

 sepals : — 

 L. 2, sessile orbicular or broadly elliptic. 

 Sep. 6-7-nerved .... 

 ft Lip much longer than lateral sepals. L. 

 more than 2 : — 

 Fls. (with ovary) 1" or less. Spm- • 75-1 • 5 

 Fls. (with ovary) 1 • 5" or more. Spur 2-4" 

 ii. Leaves clothing the stem : — 



L. hnear. Sepals -17" long. Lip -5- -7" 



broad ..... 

 L. lane. -oblong. Sep. -5" long. Lip 1" 

 broad ..... 



c. Side-lobes of lip entire, fihform : — 

 i. Anther-cells with long tubes : — 



Tall, leafy. Fls. white, lip with filiform 

 segments ...... 



ii. Anther-cells with short tubes : — 



t L. clustered, mostly above base of stem : — 

 Fls. green. Sep. • 1.5- • 17". Spur longer 



than ovary . . . . .10. furcifera. 



Fls. green. Sep. • 12-* 125". Spur shorter 



than ovary . . . . .11. affinis. 



Fls. yellow. Sep. -25". Leaf margined 12. marginata 

 tt Leaves 2 only, nerveless, appressed to 



ground . . . . . .13. diphylla. 



2. Lip entire, hnear. Stem leafy . . .14. stenantha. 



1153 



3. Susannce. 



4. platyphylla. 



plantaginea. 

 longicalcarata. 



7. longi folia. 



8. triflora. 



commelinifolia. 



