HEM 
agrées wi with thofe of the Grylli and Fulgore, syne are of 
an uniformly coriaceous texture throughout. s fur- 
ther attend to the pofition of thefe wing-cafes ain the 
reft, and the confequent form and direction of the 
in the genera C 
and as diftinctly pes 
the Coleoptera etek slong fal is aes wings, eer Iength 
and fituation, when | folded up preciaegt 7 elytra, —- an- 
hers mightb efhewn; 
but. there'is no charaéter perhaps daerehont, in which a.dif- 
rence is more fully manifefted than the ftruéture. of the 
mouth affords: Linneus, in defcribing this effential organ, 
merely tells us the mouth is bent down towards the breatt, 
an expreffion fo fugitive and unmeaning, that it cannot fail 
to ereate fome fentiment of furprife in the minds of t 
who have the means of comparing the mouth of the Gryllus 
with the Cimex, the Blatta with the Nepa, or the 20:30 
with the Fulgora, Cicada, Notoneéta, Coccus, and Cherm 
Let him beftow only a flight reflection on the diffimilarity ei 
thefe tribes in this individual refpeét, and he. will need no 
e jaws, or. man 
je d ie other 
literally of an 
infle&ed or arched, t underneath the 
in general of pretty confidezable Tength- The very form of 
this fucker determines the office it is appointed by nature to 
or and fhews that its owner is not deftined to prepare its 
thi manner on the bl of ani a as vegetable t 
. ‘The punéture and mode of feeding in that noifome 
info, the bed bug AN ore re is fufficiently ex- 
planatory of this pecu 
abhi thrips, sa 
was the firft: who endeavoured 
Pt taore. 
ers, allowing one. to retain the Linnazan nam e, anda 
ing to the other that of orthopteras This fab divifion-sns 
adopted Seige) and. being ftill continued: Latreille 
the wing-cales hali-s - coriaceous, and in 
the extremity of oe wing folds over the 
e axis, or middle pomt ors them, will fee the 
eT oe Such i is that reprefented 
' Lin 
contains falgora, cicada, cimex, nepay ay 
to combine the ad- m¢ 
vantages of the Fabrician improvements with-an arrange- ™ 
ment n nearly: correfponding with that of Linnzus. . 
With his view he divided the Linnean hemiptera into two or 
HEM 
, and the mouth furnifhed with a fheath or trunk 
ve ‘te introduction of which ey the fiefh of animals 
_and plants it derives its Shag 
_are_ clo 
n 
upper lip, ne four feelers. 
tached to each, which confirm the propriety of 
bes two orders di ftin 
HEMISPHERE, Hewnsrnsntvsy compoun nded of 
Husrus, pe te and cfaipe, Sphere, in ry,is one half of a 
globe, Hiri when divided oo two by a plane pafling 
dough’ ied cen 
f the: Give os a — be equal to the diftance of 
os et ine drawn from the centre - the 
that eae be perpendic 
making a rotation re the 
whole 
hemifphere. If the diftance of the eyes be either greater 
or leffer than the diameter of the fphere, in making fuch ro- 
tation they will =e refpectively more or lefs than a hemi- 
fphere. See Visio 
The centre. of pms of a hemifphere is five-eighths 
efteemin 
the two eyes; anda 
{phere to the middle 
line which joins the eyes 5 the 
Be ra Files diftant frem the vertex. See CentER of Gra- 
by eR, in Aflronomy, is particularly ufed for one 
half of the mundane {phere. 
The equator divides the fphere into two equal parts, called 
the vphgeit and Southern hemifpheres 
The northern hemifphere is Fehat halfin in whofe vertex is the 
D P A( Plate XVI. 
Aftronomy, fig. 140.) heer by the equator DA, an 
having the pole P in its zeni 
The fouthern ie ade, is that other half A, es 
in its zenit 
The horizon alfo whegee the aie into two hemifpheres ; 
the 
the 
ee copier Lenifpliere 3 is that alfo of the mundane {phere 
HZR, gn ag the horizon H R, and having the 
zenith Z in its vert 
The lower “hemifphere is that other half HNR » termi- 
e nated si the horizon H R, and having the nadir N in its 
4 
"ass is alfo ufed for a map,or projection, ot 
the terreftrial glo be, or half the celeitial fphere, on a 
emifpheres ~ ‘ rr called plani/pheres. 
HEMISPHER » in Geometry, fomething that 
—— to the fi sa of a nebe "put i is not juitly 
“HEMISSEN, JouHN DE, in wig he wad a painter, who is 
here becaufe of his extraordinary merit, but 
fortune, in hasibe moft of his pro- 
of children, attributed to a much 
viz, Lionardo inci ;. whence 
ape: the. dealers celal can beft ex- 
5 ke. the bdlisise aeik 4 
" ae ine verfes re- 
quire 
