Tie Htftory of ANIMALS. 157 
great, oblong, arid very flat Pearl-fhell 5. The fmall, round, varioufly coloured, 
fmooth Oflrea, with an opening near the top ; this is very uncertain in it’s colour, va¬ 
rying into red, yellow, brown, and green, and has been defcribed under thefe by 
fome, as fo many different fpecies. 6. The fmall, oval, variegated Oflrea. 7. The 
large, thin, and fmooth Oflrea, with an undulated furface, called the Saddle-oyfter. 
8. The thin, elegantly fpotted Oflrea. 9. The elegant, red, ftriated, and lineated Ja- 
ponefe Oflrea. 10. The caudated, oval-bodied Oflrea, called the Swallow-fhell. 
2. Of thofe which have the furface contabulated or plicated, but have no fpines, 
there are, 1. The large, oval, flnuated, and plicated Oflrea. 2. The thin, round, 
deeply plicated Oflrea. 3. The irregularly tortuous Oflrea, called the Leg-oyfter. 
4. The large, thick, tabulated Oflrea, with an elegantly flnuated edge. 
3. Of thofe which are of a more globofe figure, or have both fihells gibbofe and 
armed with fpines, there are, 1. The large, very gibbofe Oflrea, with rounded and 
not very numerous fpines. 2. The gibbofe and rounded Oflrea, with numerous flat¬ 
ted fpines. 3. The lefs gibbofe, flame-coloured Oflrea, with fharp fpines. 4. The 
reddifh, gibbofe Oflrea, with numerous fhort white fpines. 5. The deeply furrowed, 
purplifh-red Oflrea, with numerous whitifh, flat fpines. 6. The gibbofe, rounded 
Oflrea, with red and livid fpines. 7. The great, plicated Oflrea, with a few flat 
fpines. 8. The elegantly ftriated Oflrea, with a few fpines. 
4. Of thofe which are gibbofe and foliated, or have flat and jagged eminences in 
the place of fpines, there are, 1. The white, rounded, fcaly Oflrea, with fmall but 
elegantly flnuated foliations. 2. The fmaller gibbofe Oflrea, with foliations form¬ 
ing tubules at the ends. 3. The yellow, gibbofe, and elegantly foliated Oflrea. 4. 
The lefs, gibbofe, white and purple foliated Oflrea. 5. The little, globofe Oflrea, 
with very long foliations. 
5. Of thofe which are of an oblong figure, and have either fpines or obtufe protu¬ 
berances, there are, j. The narrow, flnuated Oflrea, with fhort and few fpines. 
2. The narrow, flnuated Oflrea, with numerous, obtufe tubercles. 3. The elegant 
Oflrea, with white foliations, edged with delicate purple fpines. 4. The variegated, 
red and white Oflrea, with large fpines. 5. The conic, deeply furrowed, fpinofe 
Oflrea. 
CHAM A. 
T H E Chama is a fhell formed of two valves, which are both convex, or gibbofe, 
and equal, and which, when fhut, leave always an opening in one part. 
Some of the Chamse are perfectly fmooth, fome are ftriated, and fome.rugofe, and 
even fpinofe 5 fome of them are oblong, others roundifh; fome equilateral, and others 
inequilateral: the feveral fpecies have very, conflderable differences in flhape, but the 
generical characters are obvious and immutable. 
Chama deprejfa Icevis^ fufca^ lineis irregular ibus nigris . 
'The fmooth^ deprejfed Chama , variegated with irregu¬ 
lar black lines . 
\\ 
This is a large fpecies; it is three inches in diameter from one extremity to the 
other, and two and a half from the hinge to the oppofite verge : the head, where the 
hinge is placed, is not in the center of the top, but near one fide : the whole furface 
of the fhell is perfectly fmooth and even, and has a fine natural polifh : it’s ground 
colour is a pale brown, and it is variegated with lines and ftreaks of black j they are 
narrow, angulated, and difpofed acrofs one another in a beautiful, irregular manner: 
their accidental meetings fometimes form refemblances of the Arabic or Arabian cha¬ 
racters, and thence the fhell has obtained the name of the Arabic or Arabian Chama. 
It is frequent on the coafts of many parts of Europe. 
Cha?na gibbofa , flriis tranfverfis nmnerofiffmh exarata . 
The gibbofe Chama , with very numerous , tranfverfe Jlrice . 
This is about two inches and a half in diameter, either way, and the fheils are both 
fo much elevated, that it’s thicknefs is not lefs than an inch : it is of a beautiful yel- 
S f low 
