350 ORCHIDACE^:. 



the column, deflected at the apex, bearded inside. Pollen 

 angular. 



A. bulbosa Linn. 



Sphagnous swamps. Can. to Car. May, June. '2J.. Scape 6 10 inches 

 high, with a globose tuber at the base, the lower part bearing 3 4 loosely 

 sheathing scales, from the upper of which there is often a linear-lanceolate 

 nerved leaf. Flowers mostly solitary, (rarely 2,) terminal, large, bright-purple. 

 Lip curled, crenulate on the margin, yellow and white, bearded in the middle. 



Bulbous Arethusa. 



13. CALOPOGON. Brown. Calopogon. 



(From the Greek caXo$- , beautiful, and 7rwywi>, a beard ; in allusion to the beard 

 of the flower.) 



Flowers resupinate. Perianth with the segments distinct 

 and spreading. Lip on the upper side of the flower, erect, un- 

 guiculate, bearded in front. Column free. Pollen angular. 



C. pulchellus Brown. Cymbidium pulchellum Willd. 



Swamps. Can. to Flor. W. to Lake Superior. June, July. 7J.. Root tu- 

 berous. Scape 1218 inches high, slender. Leaf generally solitary, 810 

 inches long, sheathing the base of the stem. Flowers 3 4, in a terminal brac- 

 teate spike, large, bright-purple. Calopogon. 



V. NEOTTE-E. Pollen powdery, granular or sectile. Anther dorsal. 



14. LISTERA. Brown. Twayblade. 

 (In honor of Martin Lister, an eminent British naturalist.) 

 Perianth irregular. Lip 2-lobed or 2-cleft, without callous 

 processes. Column wingless, (minute.) Anther fixed by its 

 base. Pollen powdery. 



1. L. cor data Brown : stem with only 2 opposite roundish cordate leaves ; 

 raceme loose; column without any appendage behind; lip elongated, 2- 

 toothed at base, deeply bifid, the segments divaricate and acute. Ophrys 

 cordata Mich. 



Sphagnous swamps. Can. to N. J. May. Q}.. Stem 4 8 inches high. 

 Leaves roundish, cordate, veined, smooth, mucronate. Raceme 7 15-flowered. 

 Flowers distant, minute, green and purple. Heart-leaved Twayblade. 



2. L. convallarioides Nutt. : stem with only 2 opposite oval-roundish 

 leaves, pubescent above ; raceme few-flowered, (4 6) ; column porrected ; 

 lip oblong, dilated and obtusely 2-lobed at the extremity. Epipactis con- 

 vattarioidcs Pursh. 



Swamps. N. Y. to Car. May. 1J-. Stem 6 inches high and very slender. 

 flowers dark-brown and green, larger than in the preceding. 



Large-flowered Twayblade. 



15. SPIRANTHES. Rich. Ladies' Tresses. 



(From the Greek (urcipa, a cord, and avOos, a/oiter ; the flowers being spiral 

 like the strands of a rope.) 



Spike spiral ; inner segments of the perianth connivent. Lip 

 unguiculate. parallel with the column, with 2 callous processes 



