MISSOURI BOTANICAL GARDEN BULLETIN 95 
sufficient to poison the = age making up the scum, 
and yet too dilute to harm the lilies. Fish are usually intro- 
duced into a water garden to keep it free from mosquito 
larve, although it should be remembered that if the pool 
is in an exposed place, subject to the action of the wind, 
there is little danger of its becoming a nuisance, since mos- 
quitoes will not breed where the water is rippling. The 
water which supplies the garden pools is furnished by a 
three-quarter-inch pipe, running very slowly. This is suffi- 
cient to keep scum from accumulating on the surface 
and supplies enough water to make up for the loss by evap- 
- oration. 
Drainage.—Water garden pools are usually located in 
rather low places, and hence, in time of rainy weather, 
receive the drainage from the adjoining slopes. The small 
pipe which takes care of the normal overflow will not carry 
off this storm water and provision must be made for the 
latter. If a large tile is so laid that its bottom is at the same 
level as the normal surface of the water, this surplus will 
usually be taken care of, although where the drained area 
is very large, more tiles may be necessary. A few heavy 
rains will soon show how much extra drainage is necessary. 
Classification of Lilies—Water lilies may be roughly 
divided into two classes—tender and hardy varieties. The 
former may be again divided into those requiring artificial 
_ heat and those that do not. The hardy lilies, of course, are 
those —— of withstanding the winter without protection. 
Practically the only water lilies that require artificial heat 
are the large-leaved Royal or Victoria lilies. Even these 
will flower and produce fairly large leaves without additional 
heat, but the results are so much better when artificial heat 
is added in cool weather, that this method of growing them 
is much practised. Heat is applied only when the normal 
temperature of the water falls below 80° Fahrenheit. 
Propagation.—Lilies are raised from seed germinated 
during the winter in tanks under glass, and the resulting 
seedlings are transplanted to the outdoor ponds late in 
the spring. Or, plants may be taken up in the fall and a 
over winter in tubs protected from frost. Once the hardy 
lilies are planted out they require but very little subsequent 
attention. 
Flowering Periods.—The lilies are peculiar as regards 
their flowering periods, and are ae characterized as 
“day bloomers” and “night bloomers.” Some of the largest 
