Species unica sectionis, Africae tropicae indigena: A. 
pusilla Summerhayes. 
Sectio 8. Coenadenium Summerhayes sect. nov. 
Plantae parvae; pedunculus rhachidem aequans vel 
brevior; sepala + inaequalia; petala ovata vel lanceolata, 
margine antico vix dilatata, subacuta; Jabellum triloba- 
tum vel integrum, lobis lateralibus brevibus dentiformi- 
bus; polliniorum viscidium commune, pro rata magnum, 
stipites saepius geniculatim conniventes. 
Species 8, Africae tropicae orientali indigenae. 
Species typica sectionis: A. breviloba Summerhayes. 
KEY TO SPECIES 
Pollinia with 2 separate stipites and viscidia 
Petals triangular or broadly triangular with the anticous margin 
much dilated, adnate to the lateral sepals along the lower anti- 
cous margin, apex acute usually sharply reflexed 
Spur 2.5 cm. or more long; relatively large plants with ligulate 
leaves 7-20 cm. in length; lip distinctly trilobed; petals 
markedly triangular; lateral sepals + spathulate, much longer 
than the dorsal sepal; peduncle long, flowers about 6-12, 
spaced out rather laxly along the rhachis 
Lateral lobes of lip from slightly shorter to slightly longer 
than the middle lobe, broad and obscurely lobulate at the 
apex; petals much broader than long; spur 5-6.5 cm. long; 
leaves usually from 1.5-2.5 em. broad, narrower in small 
individuals . . . . . . . . . . . . . .)  tenerrima 
Lateral lobes of lip much shorter and narrower than the mid- 
dle lobe, quite entire; petals about as long as broad; spur 
2.5-4.5 em. long; leaves usually 7-15 mm. broad, rarely 
broader .........2...+... 8. gracillima 
Spur less than 2 cm. long, usually much shorter 
Lateral lobes of lip well developed, never less than half the 
length of the middle lobe 
Spur shorter than the lip, much swollen at the apex; lateral 
lobes of lip about as long as or longer than the middle 
lobe; petals slightly longer than broad, 1-nerved; lateral 
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