dise minutely papillose on the inner surface near the base 
and the apex. Column deeply 8-toothed above, the cen- 
tral tooth a bristle-like continuation of the rostellum. 
Anther relatively conspicuous, shortly stipitate, orbicular- 
cordate. 
Another much smaller plant (which is apparently in- 
complete) is referable to this species. It differs from the 
type, however, in having on the lower part of the stem 
an ovate-elliptical leaf which is about 6 cm. long and 2.: 
em. wide and in having somewhat smaller flowers. 
Spiranthes densiflora appears to be rather closely al- 
lied to S. michuacana (la Llave & Lex.) Hemsl., but 
differs in its much greater height, smooth floral bracts 
and much smaller flowers with dissimilar petals. It varies 
from S. Arséniana Kriinzl. in having very different petals 
and lip. 
Mexico, State of Morelos, Tepeyte. At 2300 meters altitude. 
Flowered at Cuernavaca, October 10, 1932. Erik M. Ostlund 1513 
(Collector Carbonero) (Tyre in Herb. Ames No. 41426): State of San 
Louis Potosi, Alvarez. December 1924. C.R.Orcutt 1946 (U.S.Nat. 
Herb. No. 1209110). 
Spiranthes obtecta C. Schweinfurth sp. nov. 
Herba terrestris, foliis marcescentibus. Caulis vaginis 
albo-seariosis tubularibus lineatis omnino velatus. Race- 
mus densiflorus; flores parvi, spirales, bracteis albo-scari- 
osis omnino obtecti. Sepalum dorsale oblongo-lanceola- 
tum, coneavum, cum petalis adnatis galeam formans. 
Sepala lateralia lineari-lanceolata, acuminata, Petala el- 
liptico-linearia, leviter sigmoidea. Labellum panduratum, 
prope apicem valde recurvatum, parte inferiore cuneato- 
rhombica, parte superiore ovata cum marginibus crenu- 
latis involutis. Gynostemium generis. 
Plant terrestrial, 25-85 cm. tall. Roots very stout, 
spreading, lanuginose. Leaves apparently absent at flow- 
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