14 
Slower (Brower 
February, 1919 
Hybridizing and Crossing the French Iris. 
(Reprinted by permission from Horticulture, Boston.) 
SPORTS. 
Iris in a garden which has been prepared 
as directed in this letter is sure to sport, and 
that is one reason why the land was made 
so rich. The present arrangement of the 
parts of an Iris flower of the type with erect 
segments to the perianth is so perfectly 
beautiful, it cannot be improved. If, therefore, 
the sport results in any change in the posi- 
tion or number of the parts of the perianth, 
using this term in its strict sense, it should 
be discarded. Some kinds of Iris have a 
considerable tendency to thus sport, and 
where the ovary shows signs of having more 
than three divisions, and there are more 
than three stigmas it is possible to get a new 
type with more segments to the perianth, 
and at length to get this type to breed true. 
In my garden this has been true more fre- 
quently with the form named Khar put than 
with any other, I imagine, therefore, that 
this variety is in what de Vries calls the 
mutating stage, or is brought to this condi- 
tion by high cultivation ; a mutation plant is 
one that gets children that differ in more 
than one feature from the type and breeds 
true. 
THE THIRD STEP 
consists of writing on a painted wooden la- 
bel, the date, the names of the parents, or a 
sign to indicate this, and the number the 
flower is to have in the record book. Then 
attach the label to that particular flower, 
and make the record. Before leaving the 
flower, strip back the bud sheath— B S — 
Figure 5 — to prevent the water it will hold 
after a rain from injuring the developing seed 
pod. Then pass on, leaving the fourth op- 
eration to the plant. 
By William Rollins. 
THE FOURTH OPERATION. 
This you delegate to the flower. Soon 
after a vigorous pollen grain touches the 
sensitive surface of a stigma it begins to 
develop a tube which, 
lengthening, grows down 
through the tissue of the 
stigma until it reaches an 
ovule — shown in Figure 3 
—as one of the white dots 
in the ovary O. The end 
of the tube then opens and 
out come two bodies, the 
sperms, one of which unites 
with one part of the ovule 
and the other with another. 
This is the double fer- 
tilization of which you can 
find an account in the re- 
cent books on botany. 
When complete a new in- 
dividual has arisen. In the 
case of a cross between 
plants having differences, 
the plant when developed 
will have some of the char- 
acteristics of each parent 
and the ability to transmit 
these, though not always 
in the same combinations. 
Generally, with the com- 
mon garden Iris the re- 
sults will be different from 
what you expected. Years 
ago I bought Pallida spe- 
ciosa. From its name you 
would have thought it was 
surely the type of a true 
botanical species. Would 
you not have supposed Pal- 
lida Dalmatica was a true 
species from Dalmatia, and 
Pallida Australis a true spe- 
cies from Australia ? In 
my garden they were not 
any of them true botanical 
species, as they did not 
breed true when protected 
from Vicinists, that is other 
varieties of Iris. Beside 
Pallida, Iris comes to us un- 
der such apparently species 
names as Junonia (another 
name at one time for Pal- 
lida), Sambucina, Jacquini- 
ana, Trojana, Cypriana, 
causing the beginner to sup- 
pose that if he raises seed 
from these he will get plants 
like the parent; but if his re- 
sults are like mine he will 
get a series of severe jolts. 
They will show him what a 
long and at times weary 
journey must be taken to 
learn Irisgenealogy. Yet this 
must be pursued to the end 
before crossing can be on a 
scientific basis. Science is 
only a technical name for the 
collected results of accurate 
observations, and we gar- 
deners become scientific men 
as soon as we observe ac- 
curately. 
A TYPICAL FRENCH IRIS. 
In Figure 1 is shown a 
Lily of France of the form 
we should strive to reach 
and perpetuate. It belongs 
to a group to which I have 
given the name Athena. 
The flower resembles that of 
Pallida Dalmatica , but the last trace of purple 
that injured the drooping segments of this 
flower has been bred-out leaving the whole 
flower a clear uniform pale lavender blue, 
the Bleu Lavande, No. 204 of the Repertoire 
de Couleurs of the Societe des Francaise 
des Chrysanthemistes; though the shade is 
lighter than No. 1. The flowers are nearer 
together than in Dalmatica, making the stalk 
more impressive. Like most of the other 
species described in papers classifying Iris, 
this group does not form a true botanical 
species. The name was chosen to represent 
a new horticultural group, and used with this 
understanding is convenient. 
TIME BETWEEN POLLINATION AND FERTILIZA- 
TION. 
This period differs greatly in plant species 
from a few hours to many months. In the 
French Iris, in warm sunny weather it is 
thirty-six hours in my location— New Hamp- 
shire, latitude 44 N., elevation eleven hun- 
dred feet. In forty-eight hours the stigmas 
will have wilted to the state in Figure-7-at- 
A-, in six days to that at B-, in seven days 
to that at-C-. In nine days the developing 
ovary will begin to look like a seed pod, as 
shown at D- in the same figure Go over 
the rows every morning, cutting off the 
stigmas that have reached the condition B-, 
at the level of the stumps of the perianth 
segment. The object is to prevent dew or 
rain from injuring the developing seed-pods, 
as they will often do if allowed to remain in 
contact. When the dried stumps of the sec- 
tions of the perianth have reached the state 
at -D- cut them off at the dotted line in the 
figure. 
don’t 
pollinate Iris flowers when wet with rain or 
dew, or when rain seems near. Avoid polli- 
nating in intensely hot weather, for then the 
stigmas wilt so quickly the pollen tubes do 
not reach the ovules. Again, a very wet 
season may cause a total failure. This hap- 
pened to me in 1915. Out of several thou- 
sands of crossings no satisfactory seeds were 
