s r a 
S I E 
S I S 
6 / 8 ' 
ish claws ; the fore feet have four, and the 
. hind feet live toes. Exclusive of the general 
colour of the animal, the whole skin, when 
minutely examined, appears to be scattered 
over with very minute white specks, resemb- 
ling those on the surface of the siren lacertina. 
The sides of the body are marked by several 
strong rugs or furrows, and an impressed 
lateral line or sulcus is continued from the 
gills to the tail. 
SIREX, a genus of insects of the hymen- 
©ptera order. The generic character is, mouth 
with two strong jaws ; feelers two, truncated ; 
antennas filiform, with more than twenty-four 
joints ; piercer exserted, stiff, serrated* ; ab- 
domen sessile, pointed ; wings lanceolate, flat 
in all. 
The larvae of these insects are of a length- 
ened, cylindric appearance, living in the 
decayed parts of trees, on the substance ©f 
which they feed ; the chrysalis, as in the 
-tenthredo, exhibits the limbs of the perfect 
insect in a contracted state. 
The largest species is the sirex gigas of 
Linnaeus, which surpasses a hornet in size, 
and is principally observed in the neighbour- 
hood of pines and other coniferous trees ; it is 
of a black colour, with the eyes, the base, 
and lower half of the abdomen, bright orange- 
yellow ; the thorax villose, and the wings of 
transparent yellowish brown ; the sting or a 
terminal tube is very conspicuous. The larva, 
which measures about air inch and a quarter 
in length, is of a yellowish white colour, and 
inhabits decayed firs and pines ; at first view 
it bears some resemblance to the larvae of 
the beetle tribe, but is thinner in proportion, 
and furnished at the tip of the abdomen 
with a short black spine or process. It 
changes to a chrysalis in July, first envelop- 
ing itself in a slight silken web of a whitish 
colour. If the change to chrysalis takes 
place in summer, the fly proceeds from it in 
the space of about three weeks ; but if at the 
close of autumn, the animal continues in 
chrysalis the whole winter, emerging in the 
following spring. The male insect is con- 
siderably smaller than the female, and may 
be farther distinguished by the want of the 
caudal tube or process so conspicuous in the 
female insect ; the tip of the abdomen is also 
cf a black colour. The eggs, which are de- 
posited by the female in the decayed parts of 
the trees above mentioned, are very small, 
and of a lengthened oval shape with pointed 
extremities. 
Sirex columba is an American species, and 
is distinguished by its black body, marked 
by testaceous bands. 
Sirex pygmaais is one of the smallest of 
flie European species, being, according to 
Linnx-us, about the size of a gnat, with a black 
abdomen, marked by three yellow bands, the 
middle of which is interrupted. It is found 
in Sweden. There are seven species. 
SIRIUS, the Dog-star. See Astro- 
nomy. 
SIRIUM, a genus of plants belonging to 
the class of tetrandria and order of inono- 
gynia. The calyx is quadriful ; there is no 
corolla; the neclarium is quadriphyllous, and 
crowning the throat of the calyx ; the germen 
is below the corolla; the stigma is trilid/ and 
the berry trilocular. There is only one spe- 
cies, the myrtifolium. 
SIROCCO. The sirocco (so called by the 
Italians because it is supposed to blow from 
Syria, and in the south of France the Levant 
wind) resembles in some of its effects the 
barmattan, but differs from it in being ex- 
tremely insalubrious. It sometimes blows for 
several days together, to the great annoyance 
of the whole vegetable and animal creation ; 
its medium heat is calculated at one hundred 
and twelve degrees ; it is fatal to vegetation 
and destructive to mankind, and especially to 
strangers; it depresses the spirits in an unu- 
sual degree; it suspends the powers of diges- 
tion, so that those who venture to eat a heavy 
supper while this wind prevails, are com- 
monly found dead in their beds the next 
morning, of what is called ' an indigestion. 
The sick, at that afflicting period, commonly 
sink under the pressure of their diseases ; and 
it is customary in the morning, after this 
wind has continued a whole night, to inquire 
who is dead. 
We shall now insert an accountofthis bale- 
ful wind, from an nteresting work on the 
present slate of Sicily. 
“ The evil most to be dreaded in travers- 
ing these regions is, perhaps, the sirocco, or 
south wind, which it is imagined blows from 
the burning deserts of Africa, anil is some- 
times productive of dangerous consequences 
to those who are exposed to its fury. Dur- 
ing the continuance of this wind all nature 
appears to languish, vegetation withers and 
dies, the beasts of the field droop, the animal 
spirits seem too much exhausted to admit of 
the least bodily exertion, and the spring and 
elasticity of the air appear to be lost. The 
heat exceeds that of the most fervid weather 
in Spain or Malta, and is felt .with peculiar 
violence in the city and neighbourhood of 
Palermo. 
“ The sensation occasioned by the sirocco 
wind is very striking and wonderful. In a 
moment the air becomes heated to an ex- 
cessive degree, and the whole atmosphere 
feels as if it was inflamed ; the pores of the 
body seem at once opened, and all the fibres 
relaxed. During its continuance the in- 
habitants of Palermo shut their doors and 
windows to exclude the air ; and where there 
are no window-shutters, wet blankets are 
hung on the inside of the window, and the 
servants are kept continually employed in- 
sprinkling the apartments with water. No 
creature, whose necessities do not compel 
him to the exertion, is to be seen while this 
tremendous wind continues to blow, and the 
streets and avenues of the city appear to be 
nearly deserted. 
“ The sirocco generally continues so short 
a time in Sicily, that it seldom produces those 
complaints which are the consequence of its 
scorching heats in several parts of Italy, 
though its violence in those countries is much 
inferior to what is felt in this island. Here 
it seldom endures longer than thirty-six or 
forty hours; a time not sufficient to heat the 
ground, or the walls of the houses, in a very 
intense continued degree. It is commonly 
succeeded by the tramontane, or north wind, 
which in a short time restores the exhausted 
powers of animal and vegetable life, and na- 
ture soon assumes her former appearance. 
The cause of the sirocco wind has been fre- 
quently attempted to be explained, but the 
different hypotheses are perhaps more to be 
admired for their ingenuity and fancy than 
for being very satisfactorily explained/ The 
superior intenseness cf this scorching wirffi at 
Palermo, may perhaps be accounted for from 
the situation of that city, which is almost 
surrounded by lofty mountains, the ravines 
and valleys of which are parched and almost 
burnt up in summer. 'Die numberless springs 
of warm water must also greatly increase the 
heat of the air ; and the practice of burning 
brush-wood and heath on the neighbouring 
mountains, during the warm season, must un- 
doubtedly tend to increase the heat of the 
wind in passing over the country of Sicily, 
though it had previously been disarmed of 
part of its violence by travelling over the sea 
which divides Sicily from Africa.” 
Whether the fatal effects ®f the sirocco de- 
pend entirely upon the degree of fever which 
is produced by the extreme heat which ac- 
companies it, or whether it is really charged 
with any quantity of mephitic gas, we l/ave 
never been sufficiently informed ; but wish 
that any intelligent traveller would examine 
(lie state of the air by the eudiometer, and 
by other tests, during the prevalence of this 
wind. Should it be found loaded w ith carbonic 
gas, its ill effects might be easily obviated by 
suspending in the different apartments, cloths 
dipped m lime-water; but from the present 
state of the evidence we are disposed to think 
that all its evil consequences depend upon 
the sudden increase of die temperature 
only. 
An extraordinary blasting wind is felt oc- 
casionally at balkland s islands. Happily its 
duration is short ; it seldom continues above 
tiventv-four hours. It cuts the herbage down 
as if fires had been made under them ; the 
leaves are parched up, and crumble into dust, 
howls aie seized with cramps so as never to 
recover. Men are oppressed with a stopped 
perspiration, heaviness at the breast, and sore 
throat ; but usually recover with care. 
This account is extracted from the 
travels of Mr. Ives over land to the East 
Indies. Its fatal effects, if the statement 
is perfectly correct, evidently proceed 
from a certain portion of extremely putrid 
vapours with which it is charged, anti we sus- 
pect it only happens when a strong wind 
chances to blow over some very putrid and 
stagnant lake which is not far distant ; tra- 
vellers, however, are on such occasions' com- 
monly in a state of too much alarm to note 
circumstances with accuracy, and too much 
of their accounts is collected upoq hearsay 
evidence. This wind, after all, may only 
consist of a mephitic vapour which destroys 
life when inhaled ; and the putridity which 
is said so rapidly to take place, may depend 
more upon the climate than the nature of the 
wind. 
SISON, bastard stone-parslt y : a genus of 
plants belonging to the class of pentandria, 
and to the order of digynia; and in the na- 
tural system arranged under the 45th order, 
umbellate. The fruit is egg-shaped and 
streaked; the involucra are* subtetraphyl- 
lous. There are six species; the ainoin- 
um, inundatum, segetum, sulsum, canadense 
and ammi. The three first are natives of 
Great Britain. 1. The amomum, common 
bastard parsley, or field stone- wort, is a bien- 
nial plant about three feet high, growing wild 
in many places of Britain. Its seeds are small, 
striated, of an oval figure and bro-vn colour.' 
Their taste is warm and aromatic. Their 
