j^30 ORCIIIDACE.E. 



Order CV. ORCHIDACE^. 



Perennial herbs, with perfect irregular 3-nierous flowers, an inferior 1-celled 

 ovary with 3 parietal placeutie and very numerous ovules, 1 or 2 gynandrous 

 stamens, and waxy or more or less coherent pollen. Flowers usually inverted 

 by torsion of the ovary, the sepals and the two lateral petals similar, the superior 

 petal (ajjparently inferior) dissimilar and called the lip. Stamens coherent with the 

 style, forming the column, with usually oidy the anther opposite to the lower sepal 

 perfect and two rudimentary lateral ones (in Ci/pripedium the lateral ones perfect and 

 the third sterile) ; anthers 2-celled : pollen more or less coherent in 1 to 4 masses, 

 rarely wholly granular. Stigma obli(pie and concave, mostly viscous, the upper 

 margin often i)roduced into an erect beak. Capsule coriaceous or membranaceous, 

 dehiscing usually by 3 placentiferous valves, which separate from the persistent 

 midveins of the carpels. Seeds very numerous and minute, scobiform (like saw- 

 dust), without albumen. Stems simple or scape-like ; leaves alternate, sheathing, 

 parallel-veined, sometimes scaledike. IJoots often tuberous or thickened, some- 

 times parasitic. 



A very large order, except Graminccc the largest among Monocotyledons, occurring every- 

 where, and especially abundant in tropical America, tliough sparingly represented in the United 

 States, and still more so on the Pacific coast. 



Tribe I. M.\LAXIDEiE. Anther one, terminal and resting like a lid upon the column, 

 decid\ious. Pollen-masses 4, smooth and waxy. — Our species without green herbage (a 

 single green radical leaf in Aplcdrum and Calypso). Flowers pedicellate. 



1. Calypso. Scape 1 -flowered, from a solid bulb. Lip saccate. Column broadly winged. Pol- 



len-masses sessile on a large gland. 



2. Corallorhlza. Flowers racemose, si)iirred or gibbous at base. Lip exjianded or concave, 



biluncllate-crested. Column semiterete. Pollen-masses free, without glands. Roots 

 blanched, coralline. 



3. Aplectrum. Flowers racemose, not spurred nor gibbous. Lip expanded, deejily 3-lobed, 



3-lanullate. Column nearly terete. Pollen-masses in distinct pairs, without glands. 

 Kootstock bearing annually a solid bulb and a single large green leaf. 



Tr.lBE IL OPHRYDE/E. Anther one, connate with the column and persistent upon its face 

 immediately above the stigma. Pollun-inasses 2, of coarse grains united ])y an elastic 

 web, each mass attached at base by a stalk to a visrid gland. Stems mostly leafy and 

 flowers spieate or racemose. 



4. Habenaria. Flowers numerous, white or greenish. Lip flat, spurred. Glands exposed. 



Tribe IIL NEOTTIE/E. Anther one, erect and sessile or nearly so upon the top of the 

 column and more or less covering and declinate upon the back of the stigma, persistent. 

 Pollen-masses 2 or 4, of loosely cohering granules, becoming attached by their upper ends 

 to a viscid gland on the beak of the stigma (or remaining free in Cfjiluilantlum). Our 

 species without sjiurs, mostly somewhat pubescent. 



.5. Spiranthes. Perianth obli(iue upon the ovary, the sepals and ]ietals connivent : lip oblong, 

 embracing the column, with 2 callosities at base. Flowers small, white or greeni.sh, 

 1 - 3-rankcd in a twisted spike. Stems leafy below, from tuberous-fascicled roots. 



fi. Goodyera. Like .S/)ir<iiitlns, but lip .saccate, entire, without callosities and free from the 

 column. Leaves all radical, white-rcticulated. 



7. Liatera. Pciiauth spreading. Lip flat, 2-lobcd. Stem low, from a fibrous root, witli a pair 



iif sessile leaves in the middle. Flowers small. 



8. Epipactis. Perianth spreading and ovary rec-urved. Lip somewliat jointed in the middle, 



concave and auriculate at base, dilated above. Column short. Anther sessile behind 

 the beaked stii^ma. Stem leafy, stout. 



9. Cephalanthera. Flowers erect, the perianth more connivent. Column slender. Anther 



shortly stipitate and stigma beakless. Otherwise as Epipactis, but our species without 

 green herbage. 



