MISSOURI BOTANICAL GARDEN BULLETIN 143 
may be planted outside in shallow ponds. The plants should 
be dug in the fall before frost and divided into small sections 
for potting and storage in-the greenhouse. Copious quanti- 
ties of water should be given at this time so as to gradually 
readjust them to semi-aquatic conditions. 
TROPICAL FRUIT HOUSE 
The popularity of the tropical fruits grown in the economic 
hotise has necessitated a decided increase in the collection. 
The varied industries house has therefore been entirely re- 
planted with both the common and rarer varieties of fruits 
grown in Florida and California. Their concentration in a 
special house should afford excellent opportunity for visitors 
to study the habit of growth and flowering and fruiting 
periods of these fruits not ordinarily seen outside of the 
tropics. 
In view of the fact that especial interest is usually shown 
in the citrus plants a collection of standard varieties is 
planted in the fruit house, including orange, lemon, lime, 
pomelo and kumquat. These plants were especially grown in 
Florida for-the Garden, being twelve-months-old stock 
budded upon the sour orange stock Citrus trifoliata. This 
Species is the hardiest type known in this country—in fact, 
it is hardy as far north as Washington, D. C., and is reported . 
to withstand zero weather. It is chiefly used as a stock plant 
for the budding of various varieties, the fruits being of ex- 
cellent quality and ripening several weeks in advance of those 
on their own roots. It is considered the only stock for the 
popular Satsuma orange, due to its influence upon the hardi- 
ness, quality and quantity of the fruit. 
A recent introduction of two new species of oranges by 
E. H. Wilson from China has been secured for the Garden 
. from the Arnold Arboretum. These interesting species were 
collected in the highlands of southwest China at an elevation 
of 2000 to 5000 feet. They are not closely related to the other 
known species of the genus Citrus, and are the northernmost 
evergreen representatives of the Citrus group. Their intro- 
duction was purely for breeding purposes to further improve _ 
the hardiness of the orange and lemon. The plants are small 
trees, with long, slender spines and narrow leaves. The fruit 
is acid and of good flavor, and the seeds are rather large com- 
pared with other varieties. 
‘A noteworthy specimen of the ponderosa lemon is at the 
present time bearing many well-developed fruits. This is the 
