66 ; 
certain Orders of the Ran ales. 
Drimys Winterly Forst, and D. aromaiica , F. Muell. 
Leaf : Three large bundles, widely separated, occur in this organ ; 
between two of them, in the case of D. Winteri , occurs a tiny bundle and 
at one end of the arc a minute imperfect bundle which is evidently on the 
way to extinction. The presence of these small dwindling bundles seems to 
point to a former greater development and extension of the arc to constitute 
part of a complete cylinder. The somewhat arched character of the larger 
bundles also seem to point to a time when they were in the habit of 
abstricting off bundles on the inner side to constitute a medullary system. 
The arc unites directly with the stem-cylinder. This genus is closely allied 
to Illicium. These plants have the most modified and advanced floral 
structure of any in the order ; it is interesting, therefore, to find a corre- 
sponding and parallel advance in the vascular structure. 
D. ample xic antis ^ Vieill. 
Leaf'. In the extreme top of the petiole immediately below the 
lamina and in the midrib of the latter (the only parts of the leaf I was 
able to examine, and even that in the form of herbarium-material only) 
there is a dorsal arc of four or five bundles situated at wide distances apart. 
There is also a medullary system of three or four bundles which are but 
little smaller than those of the arc ; they are situated at varying depths, 
but none are very far from the arc ; they are also orientated in the same 
manner as the arc-bundles, although one or two lie rather obliquely. Some 
way up the midrib the arc-bundles are almost concentric, becoming very 
much inarched, which is probably due to their possessing the characteristic 
of abstricting off medullary bundles 1 ; in close proximity to one of these 
on the ventral side were two dorsally-orientated small bundles. 
The medullary bundle-system does not occur in the two species above 
described, either in the petiole or lamina, and I am unable, through lack 
of material, to say whether it occurs throughout the petiole of this species. 
It must be regarded as a primitive character and its occurrence in this 
species is probably an index to what must have been the ancestral charac- 
ter of the entire genus. D. amplexicaulis is thus more primitive in the 
vascular structure of the leaf than D. aromatica and D. Winteri. 
Lllicium florid anum^ Ellis. 
Leaf'. A single arc-shaped bundle which unites directly with the stem- 
cylinder ; this may be regarded as the most highly-modified and most 
1 This idea is a purely artificial one; phylogenetically speaking, I hold that precisely the 
reverse process is taking place, viz. fusion of the medullary with the arc-bundles. 
