SIR 
tlie nature and habits of a creature so ex- 
traordinary. The siren, if thrown with 
great force upon the ground, will break in 
several places, resembling, in this instance, 
a species of the anguis. See Amphibia, 
Plate II. fig. 3. 
S. anguina, or the anguine siren, is a na- 
tive of a particular lake in Carniola, from 
■which the water regularly drains off during 
the summer ; during which time the bottom 
produces corn, or pasture. In autumn the 
water returns with considerable rapidity, 
flowing principally from springs in the 
neighbouring mountains. In this lake this 
siren is found, of the length of eleven inches, 
and of a pale rose colour. It has both fore 
and hind legs. Its movements are extremely 
slow and weak when it is placed in a ves- 
sel, whether with or without water ; but in 
its native situation it is far more active. It 
is, by some, supposed to be die larva of a 
lizard, and by others imagined to be a com- 
■plete animal. Its habits are predatory, 
and it subsists on the smaller inhabitants ot 
the water. 
S. piscifoimis, or the fish-formed siren, is 
concluded to be a native of Mexico. In 
its general appearance it greatly resembles 
the larva of the paradoxical frog; it pos- 
sesses, however, gills with outward open- 
ings, and thus resembles a fish. The feet 
are unfurnished with the slightest degree of 
web. Shaw appears strongly inclined to the 
idea of its being the tadpole, or larva, of 
some large lizard, 
SIREX, in natural history, taUed-wasp. 
iVIouth with a thick, horny, truncate, short, 
denticulate mandible; four feelers, the hind 
ones longer and thicker upwards ; antennae 
filiform, of more than twenty-four equal ar- 
ticulations ; sting exsertedt serrate, stiff ; 
abdomen sessile, terminating in a point ; 
wings lanceolate, incumbent, the lower ones 
shorter. There are twenty-six species. The 
larvas of, this genus are six-footed, soft, and 
cylindrical ; the head rounded ; tliey perfo-' 
rate wood, and frequently eat their way into 
the bowels of other insects, and their larv® 
living upon and consuming their vitals ; the 
pupa folliculate ; the perfect insect lives on 
the nectar of flowers. The largest species 
is S. gigas, which surpasses the hornet in 
size, and is principally observed in the 
neighbourhood qf pines : it is black, with 
the eyes, the base, and lower half of the ab- 
domen, bright orange yellow. The larva^ 
inhabits decayed pines and firs. It changes 
to a chrysalis in July, first enveloping itself 
in a slight silken web, of a whitish colour ; 
SIS 
the chrysalis is of a lengthened shape, with 
antenn®, legs, and tube, very distinctly 
characterised. If the change to chrysalis 
takes place in summer, the fly proceeds 
from it in about three weeks ; but if at the 
close of autumn, the animal continues in 
the chrysalis state the whole winter. The 
male is much smaller than the female : 'the 
eggs are deposited by the female in the 
decayed parts of trees. See Plate IV. Ento-^ 
mology, fig, 5. 
, SIRIUS, the dog-star ; a very bright star 
of the first magnitude, in the mouth of the 
constellation Canis Major, or the Great 
Ilog. This is the brightest of all the stars 
in our firmament, and therefore probably, 
says Dr. Maskelyne, the astronomer royal, 
the nearest to us of them all. Some, how- 
ever, suppose Arcturus to be the nearest. 
This is one of the earliest named stars in 
the whole heavens. Hesiod and Homer 
jiiention only four or five constellations, or 
stars, and this is one of them. Sirius and 
Orion, the Hyades, Pleiades, and Arcturus, 
are almost the whole of the old poetical 
astronomy. The three last the Greeks 
formed of their own observation, as appears 
by the names ; the two others were Egyp- 
tian. Sirius was so called from the Nile, 
one of the names of that river being Siris ; 
and the Egyptians, seeing that river begin 
to swell at the time of a particular rising of 
this stai', paid divine honours to the star, 
and called it by a name derived from tliat 
of the river, expressing the star of the 
Nile. 
SIROCCO, a periodical wind which ge- 
nerally blows in Italy and Dalmatia, every 
year, about Easter. It blows from the 
south-east by south ; it is attended with 
heat, but not rain ; its ordinary period is 
twenty days, and it usually ceases at sun-set. 
When the sirocco does not blow in this 
manner, the summer is almost free from 
westerly winds, whirlwinds, and storms. 
This wind is prejudicial to plants, drying 
and burning up their buds; though it hurts 
not men any otherwise than by causing an 
extraordinary weakness and lassitude; in- 
conveniences that are fully compensated by 
a plentiful fishing, and a good crop of corn 
on the mountains. In the summer time, 
when the westerly wind ceases for a day, it 
is a sign that the sirocco will blow the day 
following, which usually begins with a sort 
of whirlwind. 
SISON, in botany, hone-wort, a genus of 
the Pentandria Digynia class and order, 
Natural order of Umbellat®, or Unibelli-j 
