38 
FLORIDA STATE HORTICULTURAL SOCIETY 
demonstration of the truth of what is 
here announced. 
COMPLEX CITRUS HYBRIDS. 
Besides the two classes of citrus hy¬ 
brids mentioned above there is a third 
containing a small proportion of trifoliata 
blood, which is likely to be of decided in¬ 
terest in Florida. These hybrids have 
been secured by crossing citranges with 
other citrus fruits not entering into the 
parentage of the original hybrid; that is, 
citranges have been crossed with the 
grapefruit on one hand, with the hope of 
securing new types of citrus fruits suita¬ 
ble to be eaten from the hand but still 
having some of the hardiness of the tri¬ 
foliata; and with the kumquat on the 
other hand in the hope of securing hardy 
forms of acid fruit's suitable for making 
ade. The kumquat has one important 
type of hardiness, ability to> resist spells 
of hot weather in winter without starting 
into growth; while the trifoliata is able 
to withstand very severe cold when in a 
completely dormant condition. 
VIGOR OF GROWTH OF CITRUS HYBRIDS 
REMARKABLE. 
An interesting thing has developed in 
connection with these hybrids: Citranges 
are more vigorous than either the orange 
or the trifoliate parent, often growing as 
rapidly as the combined growth of both 
parents. The Citrangors and second gen¬ 
eration citranges do not show this exces¬ 
sive vigor, most of them being about as 
vigorous as the parent they most resem¬ 
ble; that is, second generation citranges 
that look like oranges grow about as rap¬ 
idly as the orange. 
When citranges are crossed with a 
third species, especially if it is very dif¬ 
ferent, such as the grapefruit or kum¬ 
quat, then the hybrids which really rep¬ 
resent a commingling of three species, 
show extraordinary vigor, in some cases 
nearly equaling in growth the combined 
growth of all three parents. For exam¬ 
ple : A kumquat flower crossed June 6, 
1909, with pollen of the Rusk citrange, the 
fruit being picked the latter part of Oc¬ 
tober, 1909. The seeds were planted in 
the greenhouse of the Department of Ag¬ 
riculture on October 28th, sprouted with¬ 
in a week and in six weeks the young 
plants were strong enough to be inarched 
on two-year-old grapefruit stock. From 
the moment these seedlings appeared 
above the ground they have not ceased 
growing and are now from 2 1-2 to 3 
feet high, as large as most citrus seed¬ 
lings two years old, although they are 
barely six months old from the time of 
germination. 
Some of the hybrids made between the 
citrange and the Satsuma show some¬ 
thing of this unusual vigor, which is to 
be expected since the Satsuma is rather 
different from any of the other citrus 
fruits. 
At any rate, here we find a method of 
securing extraordinarily vigorous hybrids 
combining the qualities of three parental 
species. 
It should be stated, as mentioned in 
connection with the Citrangors, that the 
pollen of the citrange shows a wide range 
of character. If crossed on the grape¬ 
fruit, for example, some of the plants 
look much as if they were crosses between 
the orange and the grapefruit, while oth¬ 
ers are much like crosses between the tri- 
