GTXANDRIA. HEXANDRIA. 199 



scapes man\'-flowered; flowers yellow, petals spreadinpr, 

 linear and obtuse, the inner ones much narrower; lip ob- 

 corJale, spreading, obtusely 3-lobed, scarcely the length 

 otthe tube. 



An extensive genus, exclusively indigenous to the tro- 

 pical parts of America, with the exception of a few spe- 

 c.es in India. 



II.— DIANDRL\. 



622. CYPRIPEDIUM. L. Sxvartz. R. Brown. 

 Lip ventricose, inflated, saccate. Petals 4, 

 the under one bifid. The column terminating 

 behind in a petaloid lobe. 



Roots fibrous; leaves plaited, rarely radical, with the 

 scape 1-flowered, stems leafy, producing trom 1 to 3 pur- 

 plish or yellow flow ers. 



Species. 1. C candidum. 2. pai^'ifiorum. o. pv.bescens. 

 4. spectabile. 5. arietinum. Petals 5, lip saccately calca- 

 rate, stem leafy. Hab. la Canada, 6. humile. Scape 

 leafless, 1-flowered; leaves 2, radical. 



Of this singular genus there are 3 other species in Si- 

 beria, 1 in Japan, and 1 in Europe. 



Ill— HEXANDRIA. 



623. ARISTOLOCHIA. L, (Biithwort.) 



Calix none. Corolla of 1 petal, ligulate, with 

 a ventricose base. Capsule 6-celled, many-seed- 

 ed, inferior. 



Herbaceous or shrubby; stems erect or twining; leaves 

 alternate, mostly cordate and entire, rarely 3-lobed; flow- 

 ers axillary, the tube sometimes recurved. 



Species. 1. A. Sipho. ("Dutchman's Pipe.") 2. to- 

 meniosa. Obs. Stem twining, ascending to the summits of 

 the tallest trees; leaves roundish-cordate, beneath villous; 

 peduncles solitary, without bractes; corolla densely villous, 

 adscendent, border trifid, subequal, greenish-yellow, ori- 



