BOY ENING. 
lie in contact with the ground. This natural 
layering may of course be artificially imitated.— 
The dwarf box is propagated from its suckers. 
But the process of its propagation is so very easy 
and so generally known that it needs not to be 
described. 
BOXWOOD. See Box-Tree. 
BOYENING. The letting of cows’ milk toa 
professed milkman. The boyener, as the milk- 
man is called, pays a stipulated sum annually to 
the farmer for each boyened cow, and has the 
whole responsibility and charge of drawing and 
disposing of the milk; and the farmer provides 
him with lodging and implements, and gives all 
requisite pasturage, fodder, and housing to the 
cows. This curious practice is not uncommon in 
Ayrshire; and takes its name from the word 
boyn, which signifies a milk-pail. 
BRABEJUM. See Arrican ALMOND. 
BRACE. A pair or couple of bucks, hounds, 
partridges, or other animals; also, a piece of tim- 
ber or iron framed into a part of a building, or of 
any other structure, to support or strengthen it. 
BRACHYPODIUM. A genus of grasses, with 
terminal spikes, somewhat like those of wheat. 
Three species grow wild in Great Britain ; twelve 
species have been introduced from the south of 
Europe; one, from Tauria; three, from Germany; 
three, from respectively France, Barbary, and 
Mexico; and four or five more are known to bo- 
tanists. The winged species, Brachypodium pin- 
natum, formerly called Bromus pinnatus, is a per- 
ennial weed of the heaths of Britain, attains a 
height of about three feet, and flowers from June 
till August. The wood species, Brachypodiwm 
sylvaticum, formerly called Bromus sylvaticus, is a 
perennial weed of the hedges of Britain, attains 
a height of about two feet, and flowers from June 
till August. The loliaceous species, Brachypodium 
loliaceum, formerly called Triticum loliacewm, is 
an annual weed of the sea-coasts of Britain, at- 
tains a height of about one foot, and flowers in 
June and July. Most of the introduced species 
are quite destitute of interest; eight or nine of 
them are very dwarfish ; and two, B. Halleri and 
B. tenuiculum, are curious annuals. Specimens 
of the winged, the wood, and the two-spiked spe- 
cies—the last a perennial of about a foot in height 
from the south of Europe—are preserved in the 
museum of the Highland Society. The name 
Brachypodium is compounded of two Greek words 
strike root from almost all their branches which 
which signify ‘a short foot.’ 
BRACKEN. See Brake and Fury. 
BRACT, or Bractna. A floral leaf on the 
axis or footstalk of a flower. In many instances, 
it is situated on the stem of the footstalk, at its 
axis or base, and appears to the eye as if giving 
it mechanical support; in other instances, as in 
all the nigellze and some of the hellebori, it is 
situated so near the flower as to be distinguish- 
able from a calyx chiefly by its enduring as long 
as many of the common leaves, while a calyx 
eee ce Temeesenwetins 
BRAIN. 
fades at the decay of the flower or the maturing 
of the fruit ; and in a few instances, it is situated 
either on the calyx itself, as in several species of 
mussenda, or even on the fruit, as in several 
varieties of the pear. The bract of most plants 
is shaped like a leaf, though not always like a 
leaf of its own plant; and that of others is shaped 
like respectively a calyx, a scale, a thorn, and a 
flask. In most plants, it is green; in some, it is 
tinged with various shades and tints; in the lime 
tree, it is a pale yellow; in Salvia Horminum, it 
is a fine purple; and in Bartsia Coccinea, it is a 
brilliant scarlet. 
BRAIN. ‘The brain is a soft substance, partly 
reddish-grey and partly whitish, situated in the 
skull, penetrated by numerous veins, and invested 
by several membranes. Democritus and Anaxa- 
goras dissected this organ almost 3,000 years ago. 
Haller, Vicq d’Azir, and other anatomists in mo- 
dern times, have also dissected and investigated 
it without exhausting the subject. Between the 
skull and the substance of the brain three mem- 
branes are found. The outer one is called the 
dura mater. This is strong, dense, and elastic. It 
invests and supports the brain. The next which 
occurs is the tunica arachnoidea. This is of a 
pale white colour, yet in some degree transparent, 
very thin, and, in a healthy state, exhibits no | 
appearance of vessels. The membrane below 
this is called the pia mater. It covers the whole 
surface of the brain. It is very vascular, and a 
great portion of the blood which the brain re- 
ceives is spread out upon its surface in minute 
vessels. The brain consists of two principal 
parts, connected by delicate veins and fibres. 
The larger portion, the cerebrum, occupies, in 
men, the upper part of the head, and is seven or | 
eight times larger than the other, the cerebellum, | 
lying behind and below it. It rests on the bones | 
which form the cavities of the eyes, the bottom 
of. the skull and the tentorzwm, and projects be- 
hind over the cerebellum. On the whole exterior 
of the cerebrum there are convolutions, resembling 
the windings of the smallintestines. The exter- 
nal reddish substance of the brain is soft and 
vascular, and is called the cortical substance ; the 
internal is white, and is called the medullary sub- 
stance of the brain. This medulla consists of 
fibres, which are very different in different parts. 
The cerebellum lies below the cerebrum, in a pecu- | 
By examining the sur- | 
liar cavity of the skull. 
face, it is seen to be divided into a right and left 
lobe, by the spinal marrow lying between, but 
connected at the top and bottom. Like the cere- 
brum, it is surrounded by a vascular membrane, 
reddish-grey on the outside, and composed of a 
medullary substance within. In proportion to 
its size, also, it has a more extensive surface, and 
more of the vascular membrane, than the cere- 
brum. Ina horizontal section of it, we find par- 
allel curved portions of the cortical and the me- 
dullary substances alternating with each othey. 
Between the cortical and the medullary sub- 
o0d | 
