ORCHIDACEAE QUAEDAM AMERICANAE 
glottis, and Stenorhynchus. Schlechter, in his recent re¬ 
vision of the Spiranthinae, recognized four distinct groups 
of genera. By reliance on slight differences discernible in 
the structure of the gynostemium, but not always clear, 
and not always correlated with a second constant character, 
he admitted twenty-four genera, seventeen of which he 
proposed as new. That such a goodly number of heretofore 
unrecognized genera should exist in a group that has been 
intensively investigated by capable systematists, would 
indicate that deep-seated characters of value for taxonomic 
purposes have been previously neglected, disregarded, or 
overlooked. 
In facies, except for the ample sheathing bracts of the 
stem, Brachystele aguacatensis, to mention only one of the 
fourteen species admitted to the genus Brachystele in 
Schlechter’s monograph, resembles such species as Spiranthes 
Beckii Lindl. The structure of the lip is essentially that 
of Euspiranthes. Although the lateral sepals are distinctly 
coherent at base and decurrent on the ovary to form a 
small sac, this cohesion is simply a matter of degree. If 
for generic segregation reliance is placed on a peculiarity 
of the gynostemium correlated with a tendency toward 
cohesion of the lateral sepals, a character that attains its 
highest development in such genera as Sarcoglottis and 
Stenorhynchus, the risk is run of establishing genera which 
depend for recognition on a recondite character of the 
gynostemium. This seems hardly worth while if we hope 
to keep genera within the capacity to understand of those 
who identify plants. 
Spiranthes amabilis Ames sp. nov. Herba terrestris, 
folds basilaribus, scapo elongato. Racemus bi-triflorus. 
Sepala lateralia lineari-oblonga, acuta, uninervia. Sepalum 
dorsale cum petala galeam formans, lineari-oblongum. 
Petala spathulata, basi anguste lineari-oblonga, margine 
crenato-dentato. Labellum oblongum infra apicem, prope 
apicem in laminam late reniformem expansum, prope basim 
bicallosum. Gynostemium infra medium gracile. 
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