72 



BRITISH FLOWERING PLANTS 



at Pakefield, Suffolk. It is a summer plant, 

 growing in lakes, ponds, and standing water where 

 the bottom is of clay, and it flowers from June till 

 late in autumn. When the fruit ripens in autumn, 

 it sinks to the bottom of the water, but does not 

 germinate till the following spring. Then the first 

 shoot throws out roots which fix themselves in 

 the mud; and it also sprouts out digitate leaves 

 under water. After this, it sends up a stalk, 

 from which fresh shoots, leaves and stalks rise 

 till the surface of the water is reached, when the 

 true leaves at the end of the stem spread out 

 in a circle on the water. They are placed on 

 long stalks, and are trapezoidal, with denticulated 

 margins, and are thick, smooth above, and brown 

 and downy beneath. At first the leaf-stalks are 

 round, but as the flowering season approaches 

 they swell up, becoming bladder-like as the fruit 

 ripens, thus buoying up the whole plant. When 

 the fruit is quite ripe they sink down. The white 

 flowers in the middle of the floating leaves produce 

 a nut, which is first greenish black, then brownish 

 black, and very hard and angular. The nuts are 



provided with 4 horns, which are developed from 

 the calyx. They contain a white heart-shaped 

 kernel, which looks like a chestnut, and is much 

 eaten in China, to which the range of the plant 

 extends. 



Order XXX. Halurrhagacea (2 genera) 



A small Order, represented in Britain by the 

 Water Milfoils and the Mare's Tail. The Slender 

 Milfoil (Myriophyllum altemiflornni) has only 

 a few flowers on a spike, and the calyx of the 

 male flower is quadrifid. There are 4 petals, 

 8 stamens, and 4 styles. The flowers are very 

 small, and the corolla is reddish. The male 

 flowers are at first drooping, but when fully 

 developed, erect, at the summit of a spike, and 

 the female flowers form a whorl at the base. The 

 plant is common in ditches and shallow ponds, 

 and grows under water, only the flower-stalks 

 rising above the surface. There are two other 

 closely allied species in Britain, differing slightly 

 in the arrangement of the flowers. 



