thickened above, 7—8.5 mm. long, 5-6 mm. wide across 
the apex ; lamina prominently nervose, with all the nerves 
more or less raised and thickened, adorned with four 
small somewhat equal lamellae at the base of the mid- 
lobe. Column clavate, arcuate, about 1.5 em. long. 
Mexico—Nuevo Leon: Sierra Madre Oriental, lower San Francisco 
Canyon, about 15 miles S. W. of Galeana, alt. 7500-8000 ft., sparse 
in open oak wood, June 10, 1934, C. H. & M. T. Mueller 767 (Tyrr 
in Herb. Ames No. 40617); Sierra Madre Oriental, Canyon above 
Alamar, about 15 miles S. W. of Galeana, alt. 5000-6000 ft., common 
in moist open wood, June 2, 1934, C. H. & M. T. Mueller 700 (Herb. 
Ames No. 40619); Sierra Madre Oriental, Canyon de los Charcos y 
Mesa de la Camisa, above Alamar, about 15 miles S. W. of Galeana, 
rare in open oak wood in the upper canyon, June 4, 1934, C. H. & 
M. T. Mueller 733 (Herb. Ames No. 40618). 
The following key is included for convenience in iden- 
tifying all of the known species of Hewalectris. 
1. Petals linear-oblanceolate, less than 2.3 mm. broad; lip less than 
7 mm. broad 
Hexalectris parviflora 
1. Petals elliptic-oblanceolate to elliptic-obovate, 3.5 mm. or more 
broad; lip more than 8 mm. broad 
2, Lateral sepals more than 2.3 em. long; lip thickened along 
the median line and with radiating costae 
Hexalectris brevicaulis 
2. Lateral sepals less than 2 cm. long; lip lamellate 
3. Lip shallowly 3-lobed; lateral lobes of lip broadly rounded 
with the free part less than 2 mm. long 
Hewalectris spicata 
3. Lip deeply 3-lobed; lateral lobes oblong to elliptic with 
the free part more than 3 mm. long 
4. Sepals and petals strongly revolute; lip tapering at the 
base, the lamina longer than broad 
Hexalectris revoluta 
4. Sepals and petals spreading, not strongly revolute; lip 
with a slender claw, the lamina about as broad as long 
or broader 
Hevalectris mexicana 
[ 20 ] 
