624 
Notes. 
cause such a rush of air by the railway side where they grow. Seeds 
of plants which showed about a third of L. vulgaris and two-thirds of 
L. repens parentage when sown in light garden soil, yielded plants still 
nearer to L. repens ; probably they were the result of crossing with the 
pollen of L. repens. Seeds of the second generation, however, yielded 
plants nearer to L. vulgaris ; that is, they were about the same as the 
hybrid from which the first seeds had been collected. In this case 
pollen of Z. vulgaris had been kept from them. 
At Didcot the same series of hybrids has been noticed, but they 
occur in much smaller quantity. G CLARIDGE DRUCE. 
Aug. 14. 
THE ARRANGEMENT OF THE VASCULAR BUNDLES 
IN CERTAIN NYMPHAEACEAE 1 . — One of the most remarkable 
characteristics of this order is the very extensive prevalence of the 
astelic system in the arrangement of the vascular bundles of their 
stems ; however, during an examination into the structure of various 
members of the order, the fact that other systems of arrangement also 
are present came to light. Thus in Nymphaea flava and N. tuberosa 
the plants produce small tubers at the ends of stalks or stolons of 
greater or less length, and in these stalks or stolons the vascular 
bundles are not arranged in an astelic manner, but are grouped 
around three to five different centres, forming thus so many separate 
steles, or at least so many groups possessing all the characteristics of 
definite steles. Each of these is surrounded by its own endodermis, 
and is composed of three to four vascular bundles with very distinct 
and prominent phloems, while a small canal in the centre of the stele 
represents their disintegrated xylems. 
The tubers formed at the end of these stolons bear buds which grow 
out into fresh rhizomes, the first internodes of which are very narrow 
and much elongated; in these, again, the vascular bundles (four to 
seven in number) exhibit a different arrangement, for they present 
none of the confusion found in the mature rhizome, but run perfectly 
longitudinally ; either they all keep separate, or a varying number 
of them may be united to form pairs. When six of them are 
present and these are arranged in three pairs, the section presents 
1 Abstract of a paper read before Section K at the Liverpool Meeting of the 
British Association, 1896 : see also Annals of Botany, Vol. x, p. 289. 
