• -V' 
SEIl 
SER 
sum of the remaining series is equal to the 
terms so transposed.” 
Let t -[- ?-J- in inf. = S. 
^Iiiltiplying both sides by x — 1, we have 
/^2 >i»3 ff't 
z=x — l.S 
&c.' 
2 b ^ o 
or — 1 -1- -j_ 4- ^ &c. = 
X — 1.5; and if a? = 1, 
then, — 1 4- _ 1 _ + _L 4. - 1 - 4 -, &c. 
^1. a ‘ 2 !. 3^0. 4 ’’ 
= 0 ; or, 1 1 1 U, &c. in 
inf. = 1. 
SERIOLA, in botany, a genus of the 
Syngenesia Polyganiia iEquahs class and 
order. Natural order of Composit® Semi- 
flosetdos®. Cichorace*, Jussieu. Essen- 
tial character: calyx, simple; pappus sub- 
phimose; receptacle chatfy. There are 
four species. 
SERIPHIUM, in botany, a genus of the 
Syngenesia Polygamia Segregata class and 
order. Natural order of Coinpnsit® Nnca- 
mentace®. Corynibifer®, Jussieu. Essen- 
tial character: calyx, imbricate; corolla, 
one petalled, regular, seed one ; oblong, 
below the corolla. There are four species, 
all natives of the Cape of Good Hope. 
SERPENTINE, in mineralogy, a species 
'of the Talc genus : divided by Werner intp 
the common and precious: the common 
is chiefly gfeen, tliough passing into various 
other colours, which are seldom uniform. 
There are generally several colours to- 
gether, and these are arranged in striped, 
dotted, and clouded delineations. It occurs 
massive : internally it is faintly glimmering, 
which passes into dull when there are no 
foreign particles to give a slight degree of 
lustre. It is soft, not very brittle, and 
frangible. Feels a little greasy, not very 
heavy. It is infusible before the blow-pipe 
without addition. It consists of 
Magnesia 
Silica 
Alumina 
Iron 
}Vater 
101 
It is one of the primitive rocks : is found 
in many parts of Germany, Italy, Siberia, 
jn this country, Scotland, and the Shetlani} 
islands. It takes a good polish, and is turn- 
ed into vessels and ornaments of a great 
variety of shapes. In upper Saxony, several 
hundred people are employed in quarry- 
ing, cutting, turning, and polishing the ser- 
pentine which occurs in that neighbour- 
hood, and the articles into which it is manu- 
factured are carried all over Germany. The 
precious is found in Silesia. 
SERPICULA, in botany, a genus of the 
Monoecia Tetrandria class and order. Na- 
tural order of Inuudat®. Onagr®, Jus- 
sieu. Essential character; male, calyx, four- 
toothed ; corolla, four petalled ; female, 
calyx, four-parted ; pericarpium, nut tomen- 
tose. Tliere are two species, viz. S. ver- 
ticillata and S. repens. 
SERPULA, in natural history, a genus 
of the Vermes Testacea class and order : ani 
mal a terebella: shell univalve, generally 
adhering to other substances : often sepa- 
rated internally by divisions at uncertain 
distances. About fifty species have been 
enumerated. 
SERPENTE.S, in natural history, an 
order of the Amphibia, containing seven 
genera: viz. 
—0 
AchrochordiB 
Crecilia 
Amphisb®na 
Coluber 
Angiiis 
Crotalus. 
Boa 
Serpents are distinguished as footless am- 
phibia: their eggs .are connected in a 
chain ; penis frequently double ; they breathe 
through the mouth. The amphibia were 
divided by Linnmus into four orders; vis. 
Reptilia, Serpentes, Meantes, and Nantes. 
Of the meantes or gliders, which were cha- 
racterized as breathing by means of gills 
and lungs together: feet branchiated and 
furnished with claws : there was hut a 
single genus, viz. the siren : this has since 
been classed with the reptiles. See Rep- 
TiUA and Siren. 
The nant^s, or swimming amphibia, cha- 
racterized by their having fins ; and by 
breathing by means of lateral gills, were 
afterwards distributed into the orders of 
fishes denominated branchiostigi, and choli- 
dropterygii, which have since been ranked 
by Dr. Shaw and others under the general 
term cartilaginous fishes. See Chron- 
DROPTERIGIOUS. 
We have thought it right to give this ac- 
count of the changes in the Linnman system, 
which we have generally adopted, having 
omitted any mention of the facts under the 
former articles. “ Serpents,” says the trans- 
