SEEDLING STRUCTURE IN THE LEGUMINOSÆ. 13 
В. variegata, except that, owing to the shortness of the hypocotyl, the 
changes are accelerated. The structure at the collet and cotyledonary node 
is very similar in the two species, but the intervening structures are tele- 
scoped in the bypocotyl of B. Hookeri as compared with B. variegata. 
BAUHINIA ACUMINATA, Linn. 
Erect shrub. Cotyledons unfolding just above ground. 
The structure agrees so closely with that of other species of Bauhinia, 
especially B. Hookeri, that there is no need to describe it in detail. 
BAUHINIA PURPUREA, Linn. (= B. triandra, Roxb.) 
A middle-sized erect tree. This species is a close ally of B. variegata (p. 12), 
but differs markedly from that species in its mode of germination, This is 
half-epigeal, the cotyledons expanding somewhat beneath the ground, and 
turning slightly green where exposed to light. The hypocotyl is short and 
stout, and narrows rapidly at the external collet to a shortish primary root. 
The cotyledons are ovate, auricled at the base, not very thick. The epicotyl 
tapers upwards and the first internode is rather long *. 
The structure is very similar to that of B. variegata, but owing to 
the shortness of the hypocotyl the transition. phenomena are somewhat 
compressed. 
BavHINIA YUNNANENSIS, Franch. 
A woody climber. The hypocotyl is of а woody consistency, narrowing 
rapidly to a long and little branched primary root. The cotyledons some- 
times remain partially buried, sometimes spread on the surface of the ground ; 
they are ovate in shape. 
The root, a long way below the collet, is diarch, two broadly wedge-shaped 
groups of primary xylem being found enclosing a fair-sized pith. As we 
ascend to the collet the pith dilates, and the two xylems become spread out 
into long tangential bands arching round each end of the slightly elliptical 
stele. At the same time a small lateral group of xylem appears on each side 
of the stele: these groups at first consist wholly of metaxylem, but slightly 
higher up they acquire external protoxylem ; so that a transition from diarchy 
to tetrarchy is effected. 
The phloem contains, besides sieve-tubes and companion-cells, thick-walled 
* The first internode in B. purpurea. is about 30 mm. long, whereas in B. variegata it is 
олу 5mm. Thus the lengths of epicotyl and hypocotyl are in some degree complementary, 
and the first foliage leaves are carried high above the ground in both cases. Compare the 
epigeal Cesalpinia pulcherrima, whose first internode is about 15 mm. long, and the hypogeal 
C. Sappan, where it is 40 mm. long. A similar relation has been observed in Diospyros by 
Wright (1904, p. 61). 
