Off.) , 
8 E M 
SEP 
S E M 
t 'I Inis it appears that semen is composed of 
the following ingredients: 
90 water 
6 mucilage 
3 phospliat of lime 
1 soda 
100 . ■ 
Semen, ,s red. See Botany ; and Plants, 
I'kij-sioiogy of With respect to number, 
plants are either furnished with one seed, as 
sea-pink and bistort; two, as wood-roof, and 
the umbelliferous plants ; three, as spurge 
four, as the lip-flowers of Tournefort, and 
rough-leaved plants of Kay ; or many, as 
ranunculus, anemone, and poppy. The form j 
of seeds is likewise extremely various, being j 
either large or small, round, oval, heart- 
shaped, kidney -shaped, angular, prickly, 
rough, hairy, wrinkled, sic ok, or shining, 
black, white, or brown. Most seeds have 
only one cell or internal cavity; those of 
lesser burdock, valerian, lamb’s lettuce, ear- 
nriian cherry, and sebesten, have two. With 
respect to substance, seeds are either soft, 
membranaceous, or of a hard bony substance; 
as in gromwell, tamarind, and ail the nucife- 
rous plants. In point of magnitude, seeds 
arc either very large, as in the cocoa-nut, or 
very small, as in campanula, ammannia, 
rampions, and throatvvort. 
With respect to situation, they are either 
dispersed promiscuously through the pulp 
(semina nidulentia), as in water-lily ; affixed 
to a suture or joining of the valves of the 
seed-vessel, as in the cross-shaped and pea- 
bloom flowers; or placed upon a placenta or 
receptacle within the seed-vessel, as in to- 
bacco and tlfornapple. 
Seeds are said to be naked, (semina nuda) 
which are not contained in a cover or vessel. 
Such are those of the lip and compound 
flowers, the umbelliferous and rough-leaved 
plants; covered seeds (semina tecta) are con- 
tained in some vessel, whether of the capsule, 
pod, berry, apple, or cherry kind. 
A simple seed is such as bears neither 
crown, wing, nor downy pappus ; the varie- 
ties in seeds arising from these circumstances 
are particularly enumerated under their re- 
spective heads. 
In assimilating the animal and vegetable 
kingdoms, Linnaeus denominates seeds the 
eggs of plants. The fecundity of plants is 
frequently marvellous ; from a single plant or 
stalk of Indian 'Turkey wheat, are produced, 
in one summer, 2000 seeds ; of elecampane 
3000; of sun-flower 4000; of poppy 32,000 ; 
of a spike of cat’s-tail 10,000, and upwards; 
a single fruit, or seed-vessel, of tobacco, 
contains 1000 seeds; that of white poppy 
8000. Mr. Ray relates, from experiments 
made by himself, that 1012 tobacco-seeds 
are equal in weight to one grain ; and that 
the weight of the whole quantum of seeds in 
a single tobacco-plant is such as must, ac- 
cording to the above proportion, determine 
their number to be 360,000. The same au- 
thor estimates the annual produce of a single 
stalk of spleemvort to be upwards of one 
million of seeds. 
The dissemination of plants respects the 
different methods or vehicles by which nature 
has contrived to disperse their seeds for the 
purpose of increase. These by naturalists 
are generally reckoned four: 
j .Rivers and running waters. 2. The wind. 
3. Animals. 4. An elastic spring, peculiar to 
the seeds themselves. 
1. 'The seeds which are carried along by 
rivers and torrents are frequently conveyed 
many hundreds of leagues from their native 
soil, and cast upon a very different climate, to 
which, however, by degrees they render 
themselves familiar. 
2. Those which are carried by the wind 
are either winged, as in fir-tree, trumpet- 
llower, tulip-tree, birch, arbor-vita-, meadow- 
rue, and jessamine, and some umbelliferous 
plant', furnished with a pappus, or downv 
crown, as in valerian, poplar, reed, succulent 
swallow-wort, cotton-tree, and many of the 
compound (lowers, placed within a winged 
ealvx or seed-vessel, as in scabious, sea-pink, 
dock, dioscorea, ash, maple, and elm-trees, 
logwood, and woad ; or, lastly, contained 
within a swelled calyx or seed-vessel, as in 
winter-cherry, cucubalus, mel.iot, bladder- 
nut, fumitory, bladder-sena, heart-seed, and 
chick-peas. 
3. Many birds swallow the seeds of vane- 
loe, juniper, ntisletoe, oats, millet, and other 
grasses, and void them entire. Squirrels, rats, 
parrots, and other animals, suffer many of 
the seeds which they devour to escape, and 
thus in effect disseminate them. Moles, 
ants, earthworms, and other insects, bv 
ploughing up the earth, admit a free passage 
to those seeds which have been scattered 
upon its surface. Again, some seeds attach 
themselves to animals, by means of hooks, 
crotchets, or hairs: which are either affixed to 
the seeds themselves, as in hound’s-tongue, 
mouse-ear, vervain, carrot, bastard-parsley, 
sanicle, water-hemp, agrimony, arctopus, and 
verbesina; to their calyx, as in burdock, 
agrimony, rhexia, small wild bugloss, dock, 
nettle, peliitory, and lead-wort; or to their 
fruit or seed-vessel, as in liquorice, enchant- 
er’s nightshade, cross-wort, clivers, French 
honeysuckle, and arrow-ln aded grass. 
4. The seeds which disperse themselves 
by an elastic force, have that force resident 
either in their calyx, as in oafs, and the great 
number of ferns ; in their pappus, as in cen- 
taurea crupina ; or in their capsule, as in 
geranium, herb-bennet, African spine, fraxi- 
nella, horse-tail, balsam, Malabar-nut, cu- 
cumber, elaterium, and male balsam-apple. 
SEMI-CIRCLE, in geometry, half a cir- 
cle, or that figure comprehended between 
the diameter of a circle and half the circum- 
ference. 
Semi-colon,' in grammar, one of the 
points or stops used to distinguish the several 
members of sentences from each other. 
Semi-cubical parabola, in the higher 
geometry, a curve of the second order, 
wherein the cubes of the ordinates are as the 
squares of the abscisses. Its equation is 
axx—y. 
Semi-diurnal. Of any of those circles 
which the sun appears to perform each daily 
revolution, that portion which is above the 
horizon is called the diurnal arch, and that 
which is below the horizon is cuffed the noc- 
turnal arch, the halves of which are called the 
semi-diurnal and the semi-nocturnal arches. 
Semi-opal. See Opal. 
Semi-parabola, in geometry, a curve de- 
fined by the equation ax* 1 — ; as ax 2 
— y \ and «.v’' = j 4 . See the article Parabola. 
t - i , »i m • — 1 
In semi-parabolas, y • v * * ax * 
vi — I m — I m — I 
az ~ - v . z ; or the powers 
of the semi-ordinates are, ns the powers of the 
semi-abscisses, one degree lower for instance, 
in cubical semi-parabolas the cubes of the ordi- 
nates are as the squares of the abscisses ; that is- 
'y \ -v * * ,v 2 * z 2 . 
Semi- pelagians, in church history, a 
branch of the pelagians, so called because 
they pretended to keep a medium between 
the pelagians and the orthodox. 
SEMPER VIVUM, hoim-lcek, a genus of 
plants belonging to the order of dodecagynia, 
and to the class of dodecandria, and in the 
natural method ranking under the 13th order, 
succulents. 'The calyx is divided into 12 
parts; the petals are twelve; and the capsules 
twelve, containing many seeds. There are 
fourteen species; the arboreum, canariense, 
glutinosum, glanduTosmn, tectorum, globi- 
temm, viilosum, tortuosum, arachnoideum 
montanum,fedetbrme, menanthus, stcllatcinq 
and histum. 'The t ectorum alone is a native 
of Britain. It is frequent on the tops of 
houses, and flowers in July. 
SENATES AUCTO RITAS, a vote of 
the Roman senate, drawn up in the same 
form wi.h a decree, but without its force, a.s 
having been hindered from passing into a de- 
cree by some of the tribunes of the people. 
Senatus consultum, a decree of the 
Roman senate, pronounced on some ques- 
tion or point of law, which, when passed, 
made a part of the Roman law. See Civil 
Law . 
SENECIO, groundsel, a genus belonging 
to the class of syngenesia, and to the order of 
polygamia superflua, and in the natural clas- 
sification ranked under the 49th order, com- 
posite. '1 he receptacle is naked; the pap- 
pus simple; the calyx cylindrical and caly- 
culated. 'The scales are equal and conti- 
guous, so as to seem entire ; those at the ba-e 
are few, and have their apices or points de- 
cayed. There are 75 species. Of these, 
seven are British ; the vulgaris, viscosus, syl- 
vaticus, crucifolius, jacobxa, paludosus, and 
saracenicus. 
SENTENCE, in grammar, a period or 
set of words comprehending some perfect 
sense or sentiment of the mind. 
SEPIA, the cuttle-fish, &genus belonging 
to the order of vermes moljusca. There are 
eight brachia interspersed on the interior 
side, with little round serrated cups, by the 
contraction of which the animal lays fast 
hold of any thing. Besides these eight arms, 
it has two tentacula longer than the arms, and 
frequently pedunculated. The mouth is situ- 
ated in the centre of the arms, and is horny 
and hooked. The eyes are below the tenla- 
cula, towards the body of the animal. The 
body is fleshy, and received into a sheath as 
far as the breast. Their food are tunnies, 
sprats, lobsters and other shell-fish. With 
their arms and trunks they fasten themselves, 
to resist the motion of the waves. Their 
beak is like that of a parrot. The females 
are distinguished by two paps. They copu- 
late as the polypi do, by a mutual embrace, 
and lay their eggs upon sea-weed and plants* 
in parcels like bunches of grapes. Immedi- 
ately after they are laid they are white, and 
the males pass over and impregnate them 
with a black liquor, after which they grow 
