138 SIR DIETRICH BRANDIS—AN ENUMERATION 
Ihave been able to examine the internal structure of internode 
and petiole of three species—Stemonoporus Wightii, Thw. (Herb. 
Brandis), petiolaris, Thw., and reticulatus, Thw.(Herb. Mus. Brit.). 
They all have a considerable number (25-50) of resin-ducts in the 
circumference of the pith ; the ducts are somewhat unequal in size, 
the largest have a diameter of 10-15 times that of average pith- 
cells, and they are filled with a solid whitish resinous substance. 
In the lower half of the internode three of these ducts prepare 
to enter the wood, which may be seen by a fan-shaped arrange- 
ment of the medullary rays. One of these is at the apex of the 
pith, under the petiole at the top of the internode, the other two 
are lateral. Contrary to the general rule, the apical duct precedes 
the two lateral ducts; in the upper half of the internode the 
apical leaf-trace has separated from the central cylinder and has 
entered the bark, while the two lateral leaf-traces have not yet 
been formed. The apical leaf-trace very soon separates, first into 
3, and afterwards into 5 distinct vascular bundles, one at the apex 
and two at each side opposite to each other, thus resembling an 
impari-pinnate leaf. Eventually the petiole is formed exclusively 
by the apical leaf-trace. At the node the two lateral leaf-traces 
have arrived in the bark, and enter the stipules. I have also 
found branches separating from the apical leaf-trace entering 
the stipules. 
It will be a matter of considerable interest to ascertain whether 
this peculiar arrangement is common to all species of the genus. 
The petiole of S. Wightii at the base of the blade has an outer 
horseshoe of vascular bundles with 16, an inner semicircle with 
6, and a central mass with 11, total 33 ducts; that of S. rigidus 
and acuminatus has 9-11 ducts in the outer semicircle and 2 in 
the central mass (Pierre); while S. reticulatus has 13 ducts in the 
outer semicircle and none in the central mass. 
1. STEMONOPORUS Wiawrtt, Tw. Enum. Pl. Zeyl. (1859) 37 ; 
Trimen, Fl. Ceylon, i. 132.—Vateria ceylanica, Wight, Ill. i. 88; 
Dyer in Hook. f. Fl. Brit. Ind. i. 314.— Pl. III. fig. 26. 
Calyx imbricate, pubescent outside. Anthers linear, a little 
broader at base; appendix of connective short, acute. Ovary 
pubescent; style glabrous, cylindrical, furrowed, longer than 
ovary. Fruiting-calyx reflexed. Hypocotyl short, lying outside 
between the auricles of the cotyledons. Outer cotyledon slightly 
