44 MR. R. H. COMPTON: AN INVESTIGATION OF THE 
In the three seedlings examined this new fourth xylem did not divide itself 
between the two cotyledons, but passed entire to one cotyledon, joining the 
polar xylem on its way out. It should thus be compared not with a complete 
root-pole, but with half one. The other intercotyledonary xylem (third) in 
two seedlings was shared equally between the two cotyledons ; in the other 
seedling it went entire to one cotyledon (the fourth xylem going to the 
other). 
SWAINSONA CapELLL, F. Muell. (РІ. 6. fig. 93.) 
The root contains three similar 1-2-seriate xylem plates meeting in the 
centre. This structure continues some distance into the hypocotyl; the 
xylems then gradually widen out and a pith appears. — Half-way up the 
hypocotyl the xylem lies in а C-shaped figure of unusual appearance (fig. 93). 
This continues to within 2 mm. of the node, where the third xylem divides 
along the minor axis, the halves going in conjunction with the polar xylems 
to the cotyledons. The cotyledon trace is a lop-sided endarch-mesarch group 
of xylem with two obliquely-placed phloems ; the two cotyledon traces are 
separated by about 150°. 
ASTRAGALUS DANICUS, /etz., var. ALBUS. 
A herbaceous perennial with stems 10-30 em. high. The cotyledons are 
ovate, on a petiole of fair length: one edge is curved and the other almost 
straight ; it is towards the latter that the first leaf is borne. 
The root has a solid triarch xylem star which runs unchanged up the 
hypocotyl for about 10 mm. А pith then appears, and the vessels them- 
selves become intermingled with parenchyma, their reticulate structure being 
replaced by spiral. The xylem then divides itself equally between the two 
ends of the elliptical stele, the lateral group splitting along the minor axis. 
No signs of a fourth protoxylem group were detected. At the node the 
xylem is mesarch ; the bundles on one side (that of the third root-pole) are 
slightly larger than those on the other ; the phloems are obliquely dorsal to 
the xylems, and become fused in the median line higher up the cotyledon in 
the region of branching. The double bundles are not quite opposite at the 
node, but go off at an angle of about 150°. 
OXYTROPIS CAMPESTRIS, DC, 
A herbaceous perennial with woody root-stock. Hypocotyl passing 
smoothly into root. Cotyledons ovate, connate at base, slightly turned to 
опе side. 
The root has a solid triarch xylem star. The phloem contains fibres. The 
transition is high, as there is no modification of the root-structure until about 
3 mm. below the cotyledons. Then the polar xylems are separated by a 
pith and the third xylem divides itself between them ; no trace of a fourth 
