182 
AMERICAN AGRICULTURIST. 
[Mat, 
yet to be scarce. We do not often call atten¬ 
tion to plants which cannot be readily obtain¬ 
ed, unless, as in this case, we wish to stir up 
the dealers, as we have found that florists and 
seedsmen are very sure to get a plant which 
their customers call for. The engraving 
gives a flowering stem of the natural size; the 
leaves are broader than in the other; the in¬ 
dividual flowers are much larger than in any 
other, while the cluster is very compact, and 
does not become ragged as the seed-pods begin 
to form; the flowers are white, and often, espe¬ 
cially when they have been in bloom for some 
days, become tinged with rose or lilac. The 
French writers say that it should be covered 
during the winter, but it has proved quite hardy 
with us even in the severe -winter of 1874-5. 
It continues in flower longer than the other- 
perennial species, of which there are two or 
three not here mentioned, as it throws up 
side-shoots which prolong the bloom. 
How Flowers are Fertilized. 
BY PROF. ASA GRAY. 
ARTICLE IV—HOUSTONIA AND PARTRIDGE-BERRY. 
Among spring flowers many are more conspicu¬ 
ous, but few more welcome than the modest little 
Hcmstonia ccerulca , with its tiny blue and white stars 
thickly sprinkled among the earliest green of all 
flower ; figure 4, the same, laid open and enlarged, 
shows the four low stamens, at about the same 
liight as the Stigmas of the other flower. We call 
this dimorphism, which is a convenient Greek-Eng- 
for here we see a pair of flowers for each berry, so 
that the berry actually consists of two grown into 
one. This is a peculiarity of the Partridge-Berry; 
but what we are now considering is the two kinds 
FLOWERS OF THE HOUSTONIA. 
Figs. 1 and 3, Long stamens.— Figs. 2 and 4, Long styles.- 
Figs. 3 and 4, Enlarged and laid open. 
our moist pastures. They last, too, until summer 
is fairly begun. The French Canadians call them 
Bluets, but in the States they do not appear ever to 
have got any one well-recognized popular name, to 
which they have a clear title. “ Innocence" is one 
which they may share with many a simple flower. 
“ Eyehright" is not bad, but it belongs to a very 
different blossom, which is rare in this country. 
Bluets is an importation, but is coming into use, 
and is preferable to the others. But Houstonia 
itself makes as nice a common name as Mag¬ 
nolia. It commemorates Dr. Houston, an English 
surgeon and botanist, who studied under Boerhaave 
at Leyden, came to the colonies nearly 150 years 
ago, probably collected this little plant in Virginia, 
and died soon after in Jamaica. Blue Houstonia is 
not alwa 3 y s a very good name, for the blue, while 
sometimes very distinct, is sodelicato that under the 
garish sun it very commonly fades at once into white. 
We long ago noticed something odd about these 
flowers. They are perfect, that is, have both sta¬ 
mens and pistils, but they look as if they were not. 
In one clump the eye of every flower shows the tip 
of four anthers ; in another clump every one shows 
in the same place a pair of stigmas and no anthers. 
One would say these plants are male and female, 
but both have an ovary under the calyx, which sets 
a few seeds ; and, on splitting open the tube of the 
corolla, we may find in each, hidden out of sight, 
the organ it seemed to lack. Figure 1 represents 
one of the flowers with high stamens; figure 3, the 
same, laid open and enlarged, shows the short style 
and its stigmas. Figure 2 represents a long-styled 
lish way of saying that the blossoms, though per¬ 
fect, are of two kinds. 
But what is the meaning of it? At first we fan¬ 
cied that such flowers were on the way to becom¬ 
ing unisexual; that is, we thought it likely that one 
sort was «'oing to lose its pistil, and the other sort 
its stamens. And, indeed, now since we know that 
“ Nature abhors close fertilization,’' this supposi¬ 
tion might not be very unlikely. But inspection 
proved that one sort was as fertile as the other. 
For the real explanation we had to wait for Mr. 
Darwin, who, applying this principle (which he re¬ 
ceived from that prince of scientific horticulturists, 
Andrew Knight) to a similar case, that of the prim¬ 
roses, saw at once into the whole meaning of 
the thing. The gardeners had seen this ar¬ 
rangement for years and years, in the com¬ 
mon English Primrose, and called one sort 
pin-eyed , and the other thrum-eyed blossoms ; 
but Darwin first saw through it. Consider, 
that if our plants are to be of separate sexes, 
half of them cau bear no seed ; while, if 
we can make sure that hermaphrodite flowers 
shall reciprocally cross-fertilize, all may be 
fertile, and yet the whole advantage of sepa¬ 
rate sexes be secured. Now this dimorphism 
is just a contrivance for securing that. Fig¬ 
ures 1 to 4 illustrate the structure in Hous¬ 
tonia.. Before explaining the operation, let 
us look at another case of it in an equally 
pretty wild flower of a larger size, viz : in 
Mitchella repens, or Partridge-Berry, of which 
two branches are shown in figure 5. Besides 
the size and greater conspicuousness of the 
parts, the Partridge Berry, coming later into 
blossom, may be examined by our readers after the 
Houstonia has passed by, which may be the case 
in some parts of the country before this number 
comes to hand. 
The Partridge-Berry grows in woods, preferring 
much shade, and is found all the way from Canada 
to Florida, in the former coming into bloom in 
Fig. 6. Fig. 7. 
Fig. 6. Long stamen , Fig. 7, long style flower of Partridge- 
Berry enlarged and laid open. 
July, in the latter in April. Every youngster 
knows that a Partridge-Berry has two eyes, while a 
Wintergreen-Berry has only one. The explanation 
of this appears when we go back to the blossom ; 
of blossom, after the fashion of Houstonia Our 
two plants in figure 5 would never be found in the 
same patch ; for all that have come from the same 
seed are alike. The right-hand flowers have the 
four stamens on rather slender filaments, hung 
over the orifice of the corolla at considerable 
hight; the left-hand flowers have their four hairy 
stigmas—admirable pollen-catchers—raised on the 
slender style to the very same hight. Both have 
the counterpart organs lower down in the tube, 
within reach, though not in sight. To see them 
we have only to split down and spread open the 
corollas, as in figures 6 and 7, enlarged views, one 
of a long-stamened and short-styled, the other of 
a long-styled and short-stamened blossom. These 
little blossoms are most pleasantly sweet-scented, 
and therefore attractive to insects from a distance, 
and they are showy enough to attract the eye. 
This is the structure; now for the operation. 
When any flying insect* feeding by a proboscis 
or long tongue, dips this to the bottom of a 
Partridge-Berry flower, it will be likely at the same 
time to smear its face with the pollen of the high- 
anther sort, and to wipe it off on the hairy stigmas 
of the long-styled sort, and so fertilize one by the 
other. But in the very act of thus fertilizing the 
high stigmas, its proboscis will be drawn back and 
forth through the cluster of its four anthers, hud¬ 
dled together in the mouth of the tube, and the pol¬ 
len sticking to it will be conveyed in due course to 
the next blossom of the high-stamemed and short- 
styled sort, and be wiped off upon the hairy stigmas 
of that flower as it is thrust in and withdrawn. And so 
as the insect roves from flower to flower, and clump 
to clump, it must regularly fertilize the low stig¬ 
mas with pollen from the low stamens, and the 
high stigmas with the pollen of the high stamens. 
It is just the same in Houstonia, only the work is 
done by smaller insects. Here, then, is a beautiful 
illustration of “ the economy of Nature.” All the 
advantages of two sexes are fully secured, as 
fully as in the willow trees with which the bees 
are busy overhead, while smaller insects are attend¬ 
ing to the Houstonias : but in the willows half the 
plants are sterile, or staminate only, and bear no 
seeds, while here every one is fertile. Dimorphism 
is an arrangement through which flowers, by allur¬ 
ing insects to serve them, double their fertility. 
Gardening as a Business—How to Begin. 
BY FETER HENDERSON. 
In response to continued inquiries from those 
who wish to engage in gardening as a business, I 
propose to write out briefly, yet comprehensively, 
such advice and instruction as my long experience, 
together with my intercourse and correspondence 
with hundreds engaged in the various branches of 
gardening enable me to give. I find that the 
persons who desire to begin gardening as a busi¬ 
ness, are generally such as have had their tastes 
turned in that direction by being amateur cultiva¬ 
tors. Their gratuitous distributions of slips, seeds, 
or roots, to sometimes not over-grateful recipients, 
starts the idea “ that what is not worth paying for 
is not worth having,” is as true of garden products 
as of other things, and that they had better sell 
