lateral petals are altogether absent in Habenaria § Pla- 
tanthera; the marginal traces towards the dorsal sepal 
alone are present in Habenaria § Peristylus; and in some 
species of Muhabenaria, their presence is occasional and 
often they are very poorly developed. 
A transverse section passing through the gynostemium 
at the level of the stigmas (Fig. 4 F') shows the follow- 
ing four vascular traces: 
a. Al, representing the supply to the functional stamen (median) 
of the outer whorl, and 
b. G1, G2 and G3, supplying the median and lateral stigmas 
respectively. 
Generally the members of Ophrydinae possess a spur. 
Morphologically this structure is nothing but a down- 
ward outgrowth of the labellum in the form of a long 
tube or sac. Satyrium nepalense has a double spur; it is 
also dorsal in relation to the inflorescence and flower, as 
there is no resupination. Where the spur is single, the 
median trace of the labellum runs throughout its entire 
length and finally continues upwards into the labellum 
(Fig. 5 A). The marginal traces of the labellum (that are 
derived from the adjacent sepal traces), however, do not 
enter the spur but curve up into the expanded portion of 
the labellum (Fig. 5 A). On the other hand, where the 
spur is double, the median trace of the labellum does not 
enter the spur but runs straight into the median petal as 
its median trace; the marginal traces (that are given off 
by the adjacent sepal traces) run throughout the length 
of the spur on that side and then continue into the median 
petal as its marginal traces (Fig. 5 B). 
Type ILI. (Seen in the majority of monandrous or- 
chids. Fig. 4 G, H and I). The first traces to be sepa- 
rated off at the level of insertion of the perianth are those 
to the three stigmas (G1, G2 and G8), given off by the 
[73 
