Plantae terrestres, elatae; radicibus fasciculatis, stipitato- 
fusiformibus, carnosis: foliis caulinis, sursum in vaginis trans- 
euntibus; inflorescentia cylindrica, spicata, dense multiflora; 
floribus quaquaversis, in bracteas chartaceas, pulchre venosas 
omnino absconditis. 
Sepals subsimilar, connivent, somewhat arcuate, basally en- 
larged like an urn, on both sides of the flower at base becoming 
separated and form an opening like small windows, lateral 
sepals connate at base and adnate dorsally to claw of lip, 
together they form a rather prominent didymous sac. Petals 
linear, with the interior margins agglutinate with dorsal sepal. 
Lip fleshy, rather long clawed; claw arcuately recurved from 
base of column, fused with lateral sepals, together they display a 
prominent mentum; blade of lip inserted rectangularly to claw, 
conduplicate with a recurved apex, basally excavate-gibbose, the 
margins in the middle somewhat agglutinate with sides of 
column. Column rectangularly inserted on top of ovary, rather 
short, arcuate, with an oblique base, footless!, dorsally adnate to 
dorsal sepal, pubescent in front; stigmata 2, longitudinally ellip- 
tic, confluent, with a bilobed apex; rostellum rather rigid, 
oblong-linear, acuminate, quite elongate. Anther ovate, umbo- 
nate, acute; pollinia clavate, affixed to linear-oblong viscidium. 
Ovary cylindric, somewhat twisted, with an arcuate neck-like 
extension, 
Plants terrestrial, rather robust, tall, with fasciculate, stipi- 
tate-fusiform roots; leaves cauline, becoming bract-like upwards; 
inflorescence cylindric, spicate, densely many-flowered; flowers 
allsided, completely hidden in large, rather attractively veined, 
chartaceous bracts. 
TYPE: Spiranthes densiflora C. Schweinf. 
One species native to Mexico 
Index to species 
Dithyridanthus densiflorus (C. Schweint.) Garay, comb. nov. 
Basionym: Spiranthes densiflora C. Schweinf. in Bot. Mus. Leaftl. 4: 
104, 1937. 
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