LXVIIL— THE YELLOW WATER-LILY. 
Nuphar luteum Sibthorp and Smith. 
T hough classed by Linnaeus under his genus Nymphaa^ the Yellow Water- 
lilies are quite sufficiently distinct from our White Water-lily and its many 
near allies to justify their generic separation. The Arabic name Nauphar or 
Nyloufnr seems to have belonged originally to the pink-tinged White Lotus of the 
Nile {Nymph, ea Lotus Linn^). It appears in Greek form as vov(f>apy nouphar, in 
Dioscorides, and as Nenuphar is still used in France for Water-lilies in general. It 
was applied to the Yellow Water-lilies by Sir James Edward Smith in the “ Florae 
Graecae Prodromus ” in 1808. 
There are some seven species in the genus, all natives of the Northern 
Hemisphere. They have submerged leaves as well as floating ones. The former 
are thin and almost colourless, consisting of little more than two layers of epidermis 
with veins between them : the latter resemble those of Nymph,ea, but in our species 
are smaller. As the submerged leaves have no cuticularised thickening of their 
surfaces they may serve to absorb water, as is the case with those of Bladder-worts 
and other rootless aquatics, the water absorbed being also a means of introducing 
air into the plant. 
The flowers do not float like those of Nympho’a, but project a little above the 
water. Their distinctly alcoholic smell, combined, perhaps, with the flask-like form 
of the fruit, has earned the plant the name of Brandy-bottle. Their five or six 
outer perianth-leaves are arranged quincuncially^ as are the sepals of Caryophyllacea^ 
that is to say two leaves have both margins outside, two have both inside, and one 
has one outside and one inside ; and, as they are incurved, they make the flower 
into a golden globe. Within this calyx are from thirteen to twenty spirally- 
arranged, small, obovate, yellow petals, which secrete honey near the base of their 
outer, or lower, surfaces. These are followed by an indefinite series of stamens, 
also spirally arranged, so that the outer thirteen of them alternate with the petals, 
the next thirteen alternate with the first, and so on. Both petals and stamens in 
Nuphar are more distinctly hypogynous than are those of Nymph^ea. The filaments 
are short and flattened and the anthers are linear. 
The superior ovary is distinctly syncarpous, and the number of rays in the 
stigma ranges in the genus from eight to thirty ; but in the common British species, 
TV. luteum Sibthorp and Smith, there are seldom less than thirteen or more than 
twenty. In this species they do not extend quite to the margin of the stigmatic disk. 
The stigma is in a receptive condition when the flower expands, the outermost 
anthers maturing a little later, while the large size and roughened surface of the 
pollen-grains point to the entomophilous character of the flower. As in Nymphaa^ 
the chief insect-visitors are flies and beetles. 
