CLASS XVlil. ORbfeR xii. 63 



tiiSTE^RA. Corolla irregular; lip 2-lobed, sessile, ^ith no calli; column aote- 

 rous ; anther fixed by the base, (tway-blade.) 



Crani'chis. Corolla 5-petalled, resupinate, snb-ringent lip, vaulted behind 

 C. Anther inserted, terminal, n'dt caducdus ; masses of pollen farinaceous of 



Poco'nia. Petals 5, distinct, without glahds ; lip sessilCj cowled, crested inter- 

 nally ; pollen farinaceous, (snake-mouth.) 



Cymbid"ium. Petals 5, distinct; lip behind, or inverted, unguiculate ; the 

 lamina bearded ; style free; pollen angular, (grass pink.) 



Arethu'sa. Petals 5, connate at the base ; lip below growing to the stylCj 

 Cowled above, crested within; pollen angular, (arethusa.) 



Tripho'ra. Petals 5, distant, equal and connivent, without glands; lip ungui-- 

 culate, cicullate; column spatulatCj flattened, apterous, (three-bird-orchis.) 



Tipula'ria. Segments of the perianth spreading; lip entire, sessile, with a 

 tonspicuous spur at the base beneath ; column or ityle Without wings, length- 

 ened, free; anthers resembling a lid, permanent; poUini^ (or masses of pollen) 

 4, parallel, (limodore.) 



Lipa'ris. Corolla spreading; petals 5; lip flat, expanded, entire, turned vari- 

 ous ways ; column or style tvinged; pollinia 4, parallel, affixed to the summit 

 of the stigma. 



Micros"tylis. Lip flat, sagittate or deeply cordate ; column very small; 

 round ; pollinia 4, loose. 



Corallorhi'za. Lip produced behind, adnate with the spur, or free ; pollinia 

 4, oblique, not parallel, (coral-root.) 



Aplec"trum. Lip unguiculate, not produced at the base ; anther below the 

 summit of the column ; pollinia 4, oblique, lens-like. 



Calyp"so. Segments of the perianth ascending ; petals 1-sided ; lip ventri- 

 cose, spurted beneath near the end; column petaloid, dilated; pollinia 4. 



Epiden"drum. Pollinia 4, parallel, each mass with an elastic filament at the 

 base ; style united with the claw of the lip into a tube, (vanilla plant.) 



ORDER II. DIANDRIA. 



Cypripe'dium. Calyx coloured, 4-leaved, spreading; corolla 0; (by some the 

 calyx is called a corolla ;) nectary large, hollow, inflated ; style with a terminal 

 lobe, and petal-like appendage on the upper side, (ladies' slipper.)* 



ORDER v. PENTANDRIA. 



Plants bearing seeds in follicles, and pollen in masses called pollinia. 



Ascle'pias. Petals 5, reflexed ; nectaries 5, concave, erect, containing little 

 norns; each stamen with a pair of penduloils masses of pollen suspended from 

 the top of the stigma ; follicle smooth, (milk-weed, silk-weed.)t 



Apoc'ynom. Corolla bell-form ; stamens with converging anthers, proceed- 

 ing from the middle of the stigma, and alternating with 5 nectaries; stigma 

 thick, almost sessile; follicles fn pairs, long linear, (dog-bane, Indian hemp.) 



Acera'tes Corolla reflexed ; 5 concave, short nectaries; each stamen with 

 a pair of pendulous masses of pollen ; follicle smooth; corolla withptirple tips, 

 inuch longer than the calyx. 



Gonolo'bus. Corolla wheel-form, 5-parted; nectary cylindric, fleshy, 5-lobed ; 

 anthers opening transversely, terminated by a membrane; pollinia 5 pairs, not 

 separating into grains; stigma flat; follicle 2, ventricose; seeds comose. 

 (false choke-dog.) 



Periplo'ca. Calyx 5-cleft ; corolla rotate, 5-parted ; orifice surrounded with 

 an urceolate crown, terminating in 6 filiform a#ns; style 1 ; stigma 5-cornered ; 

 pollinia solitary, cotiaposed of 4 grains ; follicles 2, divaricate, (milk-vine.) 



ORDER VI. HEXANDRIA. 



Aristolo'chia. Calyx ; corolla superior, 1-petalled, ligulate, inflated at the 

 base; capsule G-celled, many-seeded, (birthwort.) 



ORDER XII. POLYANDRIA. 



As''ARtiM. Calyx subcampanulate, 3 to 4-cleft ; corolla ; anthers adnate td 

 the middle of the filaments; capsule inferior, 5-celled, crowned with the calyx, 

 (wild ginger.) 



• The la(iies' slipper of tljesarden belongs to the genus Impatiens, of the class Pentandrid. 

 f The genera in tliis order arc, by many botanists, placed in the class Pentandria. 



