Luxuriant Flowers. — If the usual number, whether of the 
petals, stamens, or pistils, proper to any flower, is un- 
duly augmented, to the exclusion or diminution of 
either of the other parts, the flower is then said to be 
luxuriant ; in which case there are three principal va- 
rieties, the multiplicate-flower, the full-flower, and the 
proliferous-flower. 
Lymphatics.— The vessels by which the sap or lymph is con- 
veyed from the extremity of the root to the extremity 
of the stem or branch, are often designated by the ap- 
pellation of Lymphatics. 
Lyrate. — Lyre-shaped. Divided transversely into several seg- 
ments, which increase towards the extremity. 
Maculae Indicantes. — The coloured spots with which many 
flowers secreting a honied fluid are marked, Springel 
designated by the name of Macula; indicantes, as 
indicating the treasure that is contained in the flower, 
and thus attracting the notice of insects. 
Margin. — The outline that bounds the expansion of the leaf or 
the petal is the margin. 
Medullary Rays. — If a horizontal section of the stem of the 
oak or elm is taken, and inspected even with the naked 
eye, it will be seen to be composed of two sets of layers 
crossing one another, the one circular and concentric, 
the other divergent from the centre. To this last set 
the appellation of medullary rays has been applied by 
some phvtologists, upon the presumption that they 
proceed from the pith, though it is hut a few of them 
that can be fairly traced to it. 
Medullary Sheath. — The first layer of longitudinal fibres 
surrounding the pith, is called the Medullary Sheath. 
Medulline. — The cellular tissue of the pith of dicotyledonous 
plants, deprived of all its juices, and no longer dis- 
charging any living function, has been regarded by 
M. Chevreul, as constituting a peculiar substance, to 
which he gives the name of medulline. But M. Ras- 
pail regards it as being merely lignin, reduced to its 
simplest form, and state of greatest purity ; so that 
we may fairly say of it, subjudice Its est. 
Membrane. — Membrane is that thin and filmy substance, of 
which the cellular tissue whether of vegetables or of 
animals is composed, being the first visible result of 
the transformation of gases, or of liquids into a solid 
and concrete form : and the primary and fundamen- 
tal basis of all organic fabrics : unless we say that the 
film is itself composed of the finest molecules imagi- 
nable, laid closely side by side. 
Micropyle. — The term micropyle, lately introduced by Mirbel, 
is equivalent to the term Foramen, formerly intro- 
duced by Grew. It is a perforation generally visible 
on the exterior of the testa, and always found facing 
the radicle of the embryo. 
Monqphyllous. — When a calyx consists of only one leaf. 
Mid-rib.— The main prolongation of the foot-stalk, which ex- 
tends from the base to the apex of the leaf, is the 
mid-rib. 
Migratory Root. — In the annual stems, which are 
partially procumbent, it often happens, that new ra- 
dicles are protruded from the lower surface of the 
procumbent portion, and part of the stem drawn down 
and converted into a root every year. The new shoot 
issues from the apex, and progresses in the same man- 
ner, so that in the course of a few years, the plant has 
actually changed its place, by so much as the stem has 
been converted into a root. Such roots are said to he 
migratory, and are exemplified in the genus Iris. 
Mildew. — Mildew is a thin and whitish coating, with which 
the leaves of vegetables are sometimes covered, oc- 
casioning their decay and death, or injuring the health 
of the plants. It is frequently found on the leaves of 
Tussilago Farfara, Humulus Lupulus, Corylus Svet- 
lana, and white and yellow Dead-nettle. It is found 
also on the leaves of wheat, in the shape of a glutinous 
exudation, particularly when the days are hot, and 
the nights without dew. Willdenow, says, it is occa- 
sioned by the growth of a fungus, of great minute- 
ness — the Mucor Erisyplie of Linnaeus, or by a sort 
of whitish slime, which some species of aphides deposit 
on the leaves. Ir. cultivated crops it is said to be pre- 
vented by manuring with soot. 
Monadelphia. — This terms gives name to the sixteenth class 
of the artificial system of Linnaeus. It implies that the 
filaments are all united at the bottom, but separate at 
the top. 
Moncecious. — Plants hearing both male and female flowers 
on the same individual, are said to be monoecious, the 
flowers being regarded as members of a family living 
in one house, as in the ease of the oak and hazel. 
Monandria. — This term gives name to the first class of the 
Linnaean system, and implies that the flowers of plants 
belonging to it, have hut one stamen. 
Monandrous. — Flowers having but a single stamen are said 
to be monandrous, as in Chara; if they have two 
stamens, as in Veronica, they are said to be dian- 
drous, and so on according to the number of stamens. 
Monocotyledonous.— Plants whose seed have only one lobe 
or cotyledon. 
Monogynous. — Flowers having but a single style are said to 
be monogynous, as in Primula. 
Monopetalous. — Flowers consisting of a single petal, or of 
several petals united, are said to be monopetalous, 
as in Campanula. When they have any other number 
of petals, they are designated according to that number. 
Monosepalous. — If the calyx of any flower consists merely 
of a single piece, or sepal, or of several sepals united, 
it is said to be monosepalous, as in Primula. If it 
consist of other numbers of sepals it is designated ac- 
cording to that number. 
Muricated. — Covered with sharp points. 
Multifid. — The margin of round leaves, cut from the apex 
almost to the base, without having any great inter- 
mediate sinuses. 
Naked Fruit. — If the fruit when it fall from the herb or tree 
is left without any extraneous or supernumerary ap- 
pendage, as in the cherry, apricot and currant, it is 
said to be naked. But if it is invested by the calyx, 
as in holly-hock, or by the corolline valves, as in the 
grape, or by the receptacle, as in the fig, it is then 
said to be coated; and if it is invested but partially, it 
is then said to be veiled, as in the case of the hazel- 
nut, which is veiled by the calyx. 
Naked Flower— When the corolla is present without the ca- 
lyx, it is denominated a naked flower, as Helleborus 
Niger. 
Naked Seeds. — Seeds destitute of a conspicuous pericarp, are 
said to be naked, or have hitherto been said to he 
so, as in the case of the Labiate, which still show tra- 
ces of a pericarp. But seeds that are truly naked, 
show no traces of a pericarp at all, the very ovula being 
naked, as in the Coniferce and Cycadece. 
Nectary. — With some flowers, there is a nectary or peculiar 
appendage, attached for the most part to the corolla, 
secreting or containing a honied juice, though it is not 
necessary to a nectary, that honey should be present. 
The horn-like process issuing from the base of the co- 
rolla of the Viola odorata, is a nectary. It assumes 
however, a great variety of shapes and situations in 
different genera of plants. In the Aconitum Napellus 
it is hooded, in the Helleborus Niger, tubular, and in 
the Sinapis Alba, a gland. 
Nerves- — The ramifications of the fibres of the petiole, as pro- 
longed throughout the expansion of the leaf, are very 
often spoken of, as being the nerves of the leaf, though 
it ca nn ot be said that they are at all analogous, in 
their functions, to the nerves of animals. 
Nucleus of the Seed. —T he nucleus is that part of ripened 
