Notes. 
3i7 
L. squarrosum, Forst, as described by C. E. Jones 1 . The material 
of L. volubile and L. salakense examined consisted of herbarium 
specimens collected by Raciborski in Java. 
L. A. BOODLE, Jodrell Laboratory, Kew. 
THU VASCULAR STRUCTURE OF THE OVULE OF 
CEPHALOTAXUS. —The seed of Cephalotaxus possesses a thick 
coat, consisting of an outer fleshy and an inner woody layer, thus 
perfectly resembling that of Ginkgo and the Cycads. This outer fleshy 
layer I regard, with Celakovsk^, as homologous with the fleshy aril 
of Taxus . Strasburger has found that the vascular bundles traversing 
this fleshy portion, one on either side of the seed, are characterized 
by their inverted orientation , i. e., by having their xylem directed out¬ 
wards, and their phloem inwards towards the woody layer of the 
seed-coat. This peculiar orientation of the bundles tends to indicate 
that the outer fleshy layer of the seed-coat is equivalent to a ligular 
structure. When ligules are sufficiently well-developed to possess 
a vascular strand, the orientation of the latter must necessarily be 
inverted in relation to the foliar organ on which they are inserted. 
The ligules of Isoetes and Lycopodiaceae have been regarded by 
(Selakovsk^ and others as homologous with the outer integument of 
ovules; the velum of Isoetes and Ferns being homologous with the 
inner integument. This view, which is most probably correct, would 
lead us to regard the outer fleshy layer of the seed-coat of Cephalo¬ 
taxus as an outer integument, for its bundles are shown to exhibit the 
orientation required by those of a ligule. 
Unfortunately, the aril of Taxus , which Celakovsk/ also regards 
as an outer integument, possesses no vascular bundles with which 
to compare those in the ovule of Cephalotaxus. But yet another 
character, which Strasburger does not appear to have remarked, in 
the outer integument (as I prefer to term it) of Cephalotaxus calls 
for special attention. As above stated, there is a single bundle on 
each side of the seed. It is greatly extended in the tangential direction, 
and situated on the innermost side of the outer and in close proximity 
to the woody inner integument. The secondary centrifugal xylem 
of the bundle is two or three layers thick. Besides this, however, 
1 C. E. Jones, British Association, Section K, 1898. Ann. of Bot. Vol. xii, p. 558. 
