H Y P 
H YE 
05 Q 
in many parts of Britain. 5. The balearicum, 
or water-leaved St. John’s wort, is a native of 
Majorca, and has a shrubby stalk, with red- 
<lioh scarified branches, small oval leaves 
"'acted underneath, and large yellow flowers 
appearing great part cf the year. 0. The 
monogynum, or one-styled China livperi- 
cum, has a shrubby purplish stalk, about two 
ieet high, and clusters of small yellow flow- 
ers, with coloured cups, and only one style, 
flowering the greatest part of the year. 
1 he tutsan long held a place in the medi- 
cinal catalogues ; but its uses are very little 
thought ot at present. The leaves given in 
substance are said to destroy worms. By 
distillation they yield an essential oil. The 
flowers tinge spirits and oils of a fine purple 
colour. Cows, goats, and sheep eat the 
plant; horses and swine refuse it. The dried 
plant boiled in water with alum dyes yarn of 
a yellow colour ; and tiie Swedes give a fine 
purple tinge to their spirits with the flowers. 
HYPHYDRA, a genus of the class and 
order monoecia gynandria ; the male cal. is 
one-leafed ; cor. none ; stam. six. The fe- 
male no cal. or cor. ; caps, one-celled. There 
is one species, a little aquatic plant of Gui- 
ana, of no note. 
HYPNUM, feather-moss; a genus of the 
natural order ot musci, belonging to thecryp- 
togamia class of plants. ’I he anthera is oper- 
cuiated, or covered with a lid ; the calvptra 
smooth; the filament lateral, and rising out 
of a perichxtium, or tuft of leaflets different 
from tne other leaves of the plunt. T. here ure 
fifty species, many of them natives of Great 
Britain ; none of them, however, have any re- 
markable property, except the proliferum 
and parietinum. The first is of a very singu- 
lar Structure, one ghoot growing out from the 
centre of another; the veil is yellow and 
shining; the lid with a kind of long bill; the 
leaves not shining ; sometimes of a yellowish, 
«md sometimes of a deep green. This moss 
covers the surface of the earth in the thickest 
shades, through which the sun never shines, and 
where no other plant can grow. The second 
lias shoots nearly flat and winged, undivided 
lor a considerable length, and the leaves slrin- 
ing ; but the old shoots do not branch into 
new ones as in the preceding species. It 
grows in woods and shady places ; and, as 
well as the former, is nsed for filling up the 
chinks in wooden houses. 
PTY POCAUSTUM, among the Greeks 
and Romans, a subterraneous place, wherein 
was a furnace, to heat the baths. 
HY POCHJER1S, havvk’s-eye ; a genus of 
the polygamia requalis order, in the syngene- 
sis class of plants ; and in the natural method 
ranking under the 49th order, composite. 
'Phe receptacle is paleaceous; the calyx a 
little imbricated ; the pappus gluiny. There 
are five species ; none of which have any re- 
markable property, except the maculata, or 
spotted havvk’s-eye. It is amative of Britain, 
and grows on high grounds. The leaves are 
boiled and eaten like cabbage. Horses are 
fond of this plant when green, but not when 
dry. Cows, goats, and swine eat it; sheep 
are not fond of it. 
HYPOCHONDRIA. See Anatomy 
and Medicine. , 
HYPO I HENySE, in geometry, the 
longest side of a right-angled triangle ; or it 
is that side which subtends the right an fle. 
Euclid, lib. 1. proposition xlvii. demon- 
strates, that, in every rectilinear right-angled 
triangle, the square of the hvpotheouse is 
equal to the squares of both the' other sides. 
This celebrated problem was discovered by 
Pythagoras, who is said to have sacrificed a 
hecatomb to the Muses, in gratitude for the 
discovery. 
HYPOXIS, a genus of the monogynia 
order, in the hexamlria class of plants; and 
in the natural method ranking trader the 10th 
order, coronariae. The corolla is divided into 
six parts, and persisting, superior ; the cap • 
side narrowing at the base; the calyx a bi- 
valved glume. There are fourteen species, 
bulbs of America and the Cape. 
HY RAX. Hyrax, a genus of quadru- 
peds of the glires’ order. The generic cha- 
racter is, front teeth in the upper jaw two, 
broad, somewhat distant ; in the lower jaw 
four, broad, flat, twice crenated; grinders 
large, four on each side in botli jaws ; fore- 
feet with four toes; hind-feet with three 
toes; tail none; clavicles none. This genus 
is distinguished from all the rest of the glires 
by the remarkable circumstance of having- 
four teeth in the lower jaw instead of two: 
these lower teeth are also of a different struc- 
ture from the upper, being broad, short, and 
crenated or denticulated at the top : the up- 
per teeth in this genus are also less sharp or 
pointed than in the rest of the glires. In 
other particulars the genus hyrax seems most 
nearly allied to that of cavia. The most re- 
markable species are : 
1. Hyrax Capensis is a native of moun- 
tainous situations about the Cape of Good 
Hope ; residing in the hollows of rocks, and 
leaping with great agility about the promi- 
nences of the irregular regions it frequents, 
though its general or walking pace is not re- 
markably quick. Its 'size isfe'^arly that of a 
rabbit, and in colour it much ts ^enables that 
animal, but is whitish beneath'. It is said to 
be known at the Cape by the name of rock 
badger, but Mr. Allamand observes, that 
this is an improper name, since the structure 
of its feet evidently shews that it has no power 
of digging or burrowing. It is a diurnal ani- 
mal, and by night retires into the cavities of 
rocks, &c. 
This animal appears to be easily tamed, 
and in that state is observed to be remarka- 
bly cleanly, and of a lively and active disposi- 
tion; leaping almost as readily and with as 
much security as a cat. 
2. Hyrax Syriacus, or Syrian hyrax, seems 
to have been first clearly described by Mr. 
Bruce, in the appendix to his celebrated 
Abyssinian Travels. It is found in Ethiopia, 
in the caverns of the rocks, or under the 
great stones in the Mountain of the Sun, be- 
hind the queen’s palace at Koscam. It is 
also frequent in the deep caverns in the 
rock in many other parts of Abyssinia. It: 
does not burrow or make holes, as’the rat and 
rabbit. 
In the place of holes, it seems to delight in 
less close, or more airy places, in the mouths 
of caves, or clefts in the rock. Thev do not 
stand upright upon their feet, but seem to 
steal along as in fear, their belly being nearly 
close to the ground, advancing a few steps at 
a time, and then pausing. They have some- 
thing very mild, feeble, and timid, in their de- 
portment; are gentle and easily tamed, though, 
when roughly handled at the first, they bite 
very severely. The hyrax is supposed to 
IT Y S 
be the animal erroneously called by ouv 
translators of the bible cunicuius, the rabbit 
or coney. See Plate Nat. Hist. fig. 230. 
3. Hyrax Hudsonius. Jts colour isacine* 
reous brown, with the ends of the hairs white. 
It is a native ot Hudson’s Bay. Its size is 
nearly that of a common marmot ; the feet 
are tetradactylous ; of a similar form to those 
of the cape hyrax, but have rounded claws 
on ail the toes. 
HY'SSOPUS, hyssop, a genus of the 
gymnospermta order, in the didynamia class 
ot plants; the cor. has the lower lip with a 
small cremate segment; stam. straight, distant. 
1 here are three species ; but only one of 
them, viz. the officinalis, or common hyssop 
is cultivated for use. Besides possessing the 
general virtues of aromatics, they have been 
supposed useful in humoral asthmas, coughs, 
and other disorders of the lungs; and are 
said to' promote expectoration. 
HY STERICS. See Medicine. 
HY STRIX. Porcupine, a genus of 
quadrupeds, of the order glires. The ge- 
neric character is front-teeth two, both in the 
upper and under jaw, obliquely cut; grinders 
eight ; body covered with spines intermixed 
with hairs ; four toes on the fore-feet ; five on 
the hind. 
. 1- Common porcupine. From their ob- 
vious external characters alone, without re- 
ference to the form and disposition of the 
teeth, the porcupine and the hedgehog mi girt 
be .placed together ; but .such is the dissimi- 
larity of these organs, tlrat the one must of 
necessity belong to the Linnaean order ferae 
and the other to that of glires. 
The singular appearance of the porcupine, 
so different from that of the generality of 
quadrupeds, must in the earliest ages have 
attracted the attention even of the most in- 
curious ; the variegated spines or quills with 
which it is covered, naturally suggesting the 
idea of a fierce and formidable animal : '"it is, 
however, of a harmless na'ure, and the quills 
are merely defensive weapons, which, when 
disturbed or attacked, the animal erects,, and 
thus endeavours to repel his adversary. 
1 ne general length of the porcupine is 
about two feet from head to tail, and that of 
the tail about four inches. The upper parts 
of the animal are covered with long, hard, 
and sharp quills; those towards the middle 
and hind part ot the body being longer than 
the rest, and measuring from nine or ten to 
twelve or fifteen inches in length : they are very 
sharp-pointed, and are variegated with several 
alternate black and white rings: the root, or 
point of attachment, is small -."the head, belly, 
and legs, are covered with strong dusky 
bristles, intermixed with softer hairs : on the 
top of the head the hairs are very long, and 
curved backwards in the manner of a ruff or 
crest: the ears are short and rounded: the 
nose blunt; the upper lip divided by a 
strongly-marked furrow ; the two fore-teeth, 
both above and below, extremely large and 
strong: the fore feet have four toes; the hind 
feet five; all armed with strong crooked 
claws : the tail is covered with short aud ra- 
ther flatfish quills, which are often abrupt or 
truncated, rather than pointed at the extre- 
mities. This animal is a native of Africa, In- 
dia, and the Indian islands: it is also found in 
some of the wanner parts of Europe, and is 
said to be not very uncommon in Italy and 
