62 
AMERICAN AGRICULTURIST. 
[February, 
delpliia, one of the early American botanists. 
When these plants were carefully studied by 
Torrey and Gray, they found no good distinc¬ 
tions to separate Nuttall’s Bartonia from the 
earlier Mentzelia of Linnaeus, and besides Bar¬ 
ton’s name had already been previously applied 
to another, and quite different plant, and it 
had to be dropped. This is a matter of regret, 
as we should much prefer to have the name of 
Barton borne by some of the finest of our na¬ 
tive plants, than as now, by some of the most 
humble, but such matters are not governed by 
preferences, but by rule. The name Bartonia 
is still continued in the seed catalogues, for 
plants which are properly Mentzelias. As 
many persons, even some who have passed their 
lives in the cultivation of plants, cannot under¬ 
stand why a name once given to a plant should 
not be retained by it ever after, we give the 
above bit of nomenclature to show that these 
changes are not matters of fancy, and are never 
made—at least never by botanists of eminence 
—without sufficient reason. In this case there 
are two reasons, either of which would suffice: 
firstly, the plants which Nuttall called Bartonia 
are not distinct from Mentzelia, and secondly, 
Muhlenberg had given Barton’s name to a little 
Gentian-plant, about a dozen years before 
Nuttall applied it to the plants in question. 
The' Mentzelias belong to the Loasa Family, 
which need not be described, except to say, 
that they are herbs, often with stinging bristles., 
and related to both the Evening Primrose 
Family and to the Cactus Family, in some re¬ 
spects. The genus Mentzelia includes annuals, 
biennials, and possibly some are perennials, 
with alternate, mostly lobed leaves, which, as 
well as the stem, are clothed with rough bris¬ 
tles. These bristles, by the way, are in some 
species most interesting objects for the micro¬ 
scope, as they present a great variety of elegant 
and curiously formed hooks and barbs. The 
yellow or white flowers have from five to ten 
petals, and many stamens, all upon an ovary 
which ripens into a few- or many-seeded pod. 
Mentzelia Lindleyi, which is “ Bartonia aurea ” 
of the catalogues, is an annual from California, 
one to two feet high, with bright yellow five- 
petalled flowers, opening in sunshine, and is a 
pleasing plant. The finest species of all is 
Mentzelia ornata, a biennial, if not perennial. 
It grows four or five feet high, branches freely, 
and bears large creamy-white flowers which 
open at sunset, or earlier on a cloudy day. The 
engraving, being much reduced in size, while 
it gives the shape, fails to convey an idea of the 
exceedingly showy character of the flower. 
There are ten petals, at least two inches in 
length, rather firm and papery in texture, and 
within these there is a crowd of 200 or 300 
stamens, remarkably long, erect, and stiff, giv¬ 
ing the flowers somewhat an artificial look, and 
from the number of stamens they resemble 
some cactus flowers. They are very strongly, 
and pleasantly fragrant. This species is called 
ornata, meaning furnished, on account of the 
leafy bracts beneath the flower. A related and 
similar species, with flowers about half the 
size, is without the bracts below the flower, 
and is called M. nuda, or naked Mentzelia, and 
though greatly inferior to the other seems to be 
better known in cultivation. Both species are 
found in Nebraska and southward. Though 
biennials, they will, if the seeds are sown early 
under glass, bloom the same year, but their 
flowering will be much later than if sown in 
August or September, to bloom the next year. 
It would be safer to winter the plants in pots 
in a frame, but if left in the open ground they 
should have a dry spot, as there is danger that 
their fleshy roots may decay if too wet. The 
plant branches freely, and should not stand 
closer than three feet. The English horticul¬ 
tural journals notice the failure of M. ornata to 
flower with them, their climate being too cool 
for it—a marked contrast with our own success 
last summer, when a row, 50 ft. long, was to¬ 
wards sunset sheeted with bloom, and present¬ 
ed a sight worth going far to see. A corre¬ 
spondent of the “ Garden ” quotes a Dr. Bell 
as authority for the statement that the plant is 
“ called by the ranchmen the Prairie Lily,” a 
name that we have not before heard for it, and 
which is such a thorough misnomer that it 
should be suppressed. The same author states 
that the odor is oppressive and causes violent 
headache, a peculiarity we have not noticed, 
and probably like many other odors it un¬ 
pleasantly affects only certain individuals. 
How Flowers are Fertilized. 
BY PROP. ASA GRAY. 
ARTICLE X.—THE BUSY BEE. 
The season of flowers had passed and winter was 
upon us before we could reach the most curious 
and special of all the arrangements by which in¬ 
sects are made to fertilize blossoms, namely, that 
in which they carry all the pollen of a flower in a 
mass from one plant to another. This is just what 
is done in two large families of plants, viz. : the 
orchis and the milk-weed families. They are wide¬ 
ly different from each other in other respects, but 
they agree in this. Perhaps, when the season 
comes round, we may take some of these cases in 
hand. But for the present we have had cases 
enough, and in sufficient variety, to raise several se¬ 
rious questions. First of all, what is the good of 
cross-fertilization ? To impart new vigor, is the 
answer that we have all along given. But where 
is the proof that crossing does invigorate ? More¬ 
over the cases in which flowers must needs be cross- 
fertilized, shade off into those in which they mere¬ 
ly may cross now and then, and are matched by 
another kind of case, in which they must self-ferti¬ 
lize. If, on the one hand, many blossoms are as 
plainly adapted for cross-fertilization “ as the teeth 
and talons of a carnivorous animal are adapted for 
catching prey,” we must admit that there are others 
in which self-fertilization is just as clearly aimed 
at. How are these cross purposes in Nature to be 
reconciled ? Then, how and why does crossing 
give new vigor ? In most plants—at least in large 
herbs and in trees and shrubs, with their hundreds 
and thousands of flowers—the most likely crossing 
is that of blossoms on the same tree, or the same 
branch or cluster. Is such near crossing as ser¬ 
viceable as that between the flowers of separate 
plants ? And if not, why not ? Finally, consider¬ 
ing the multitude of flowers which most plants 
bear, and the short time each is in blossom, is it at 
all likely that most or many of those which are 
said to need help will actually be visited by insects ? 
Now most of these questions have been taken up 
and answered by Mr. Darwin in a book just pub¬ 
lished, entitled ‘‘The Effects of Cross and Self- 
Fertilization in the Vegetable Kingdom.” Our 
readers will be interested to know what Mr. Darwin 
has to say upon these questions. 
We take the last question first; and cull the fol¬ 
lowing from the Xlth chapter of this new book, 
which treats of “ the habits of insects in relation 
to the fertilization of flowers.” 
In this kind of work, and in other respects, bees 
are the most knowing and the most useful of in¬ 
sects. “All kinds of bees, and certain other in¬ 
sects, usually visit the flowers of the same species 
as long as they can,, before going to another spe¬ 
cies.” It appears that Aristotle observed this with 
respect to the hive-bee more than 2,000 years ago ! 
It does not bold true without exception, but is gen¬ 
erally true. This is very good for the flowers, as it 
greatly favors the cross-fertilization pf distinct in¬ 
dividuals of the same species, and avoids waste of 
pollen. But why do the bees do it ? To save time. 
They have just learned howto stand in the best po¬ 
sition on the flower, and how far and in what di¬ 
rection to insert their proboscis ; and so they will 
work much quicker than if they were to take dif¬ 
ferent flowers promiscuously, each kind requiring 
different management. This explanation was hit 
upon independently by Mr. Darwin and H. Muller. 
“ Humble and hive-bees are good botanists; for 
they know that varieties may differ widely in the 
color of their flowers, and yet belong to the same 
species.” They have been repeatedly seen to go 
straight from a red Fraxinella plant to a white one, 
from a dark purple Pansy to a bright yellow one, 
etc. This is the more curious, because Lubbock 
has shown that bees distinguish and are very much 
guided by colors ; and when Mr. Darwin cut away 
the blue petals of Lobelia LJrinus, and Mr. Anderson, 
the corolla of a Calceolaria, the bees ceased to visit 
them. That color is not the only guide is also 
shown by bees flying straight from one clump of a 
yellow Evening Primrose to every ‘other clump of 
the same plant in the garden, not turning aside to 
Eschscholtzia—flowers which they passed close by. 
But how did the bees discover that red and white 
Fraxinellas belong to the same species ? They 
probably have a keen sense of odors, and Fraxi¬ 
nellas are strong-scented; but that will not ex¬ 
plain the remarkable fact, vouched for by H. 
Muller, that bees collecting pollen from primroses, 
“invariably passed by the flowers of the long- 
styled form, in which the anthers are seated low 
down in the tubular corolla. Yet the difference 
in aspect between the long-styled and the short- 
styled forms is extremely slight.” 
The industry of bees is proverbial. But some of 
the facts, which Mr. Darwin has himself observed, 
give us a still higher idea of it. They appreciate 
the value of time. When flowers, such as Colum¬ 
bines, have several nectaries, if they find one ex¬ 
hausted by other bees, “they do not try the others, 
but, as I have often observed, pass on to another 
flower. ” “ Humble-bees fly at the rate of ten miles 
an hour. ” Does any one know the rate at which 
hive-bees fly ? As to the number of flowers visited 
in a given time, Mr. Darwin observed that in exact¬ 
ly one minute, a humble-bee visited 24 flowers of 
Linaria Cymbalaria; another, 22 flowers of Snow- 
berry ; a third, 17 flowers of Larkspur on two 
plants. Watching a single flower of Evening Prim¬ 
rose, he saw it visited eight times in 15 minutes by 
several humble-bees, and, in following the last of 
these bees, he found that in a few additional min¬ 
utes it visited every plant of the species in a large 
flower-garden. In one mmute, six bell-flowers were 
entered by a pollen-collecting hive-bee, although 
gathering pollen is much slower work than sucking 
nectar. Within ten minutes seven flower-stalks of 
a Fraxinella were visited by 13 humble-bees, each 
of which entered many flowers. A few days after¬ 
wards, the same plant was watched for ten minutes, 
and 11 humble-bees visited the flowers. Mr. Dar¬ 
win computed that each flower of this Fraxinella 
must have been visited at least thirty times a day, 
and the same flower keeps open during several 
days. From these examples we learn what efficient 
fertilizers bees must be. 
A few words about the habit which some bees 
have of taking their wages while shirking their work. 
In all honey-bearing blossoms there is a proper 
mode of access, which most insects avail them¬ 
selves of according to their ability and opportunity. 
But bees are very apt to enter in some other way, 
especially by perforating the tube or base of the 
corolla. Almost every one has observed this in bean 
blossoms, and here the structure of the flower is 
such that the larceny may save time ; and the same 
may be said of red clover, in which occasionally 
most of the blossoms examined are found to have 
been perforated and rifled. But it is also done in 
simpler flowers, where it would seem that the sec- 
tar might be honestly come by with quite as little 
trouble. 
As far as Mr. Darwin knows, it is always humble- 
bees which bite the holes ; but hive-bees are quick 
to take advantage of it,—and not slow to learn the 
trick, it seems, for H. MuJJer hqs seen them bite 
