233 
ECHINUS. 
avenues flattifh ; crown central. Inhabits the Adriatic : 
refembles echinus craniolans. V 
82. Echinus ovulum : furface pulvinate ; circumference 
obtufely oval; bafe globular; fides (lightly grooved; 
crown central. Perhaps a variety of echinus craniolaris. 
83. Echinus lathyrus: furface and bafe pulvinate, cir¬ 
cumference oval; fides (lightly grooved ; avenues pulvi¬ 
nate; crown nearly central. Shell dull yellowilh-grey, 
and of a middle fize between echinus nucleus and cranio¬ 
laris. 
84. Echinus equinus : furface and bafe pulvinate, cir¬ 
cumference elliptic ; (ides fmooth ; avenues fubpulvinate; 
crown central. 
85. Echinus minutus : furface pulvinate and nearly flat, 
circumference ovate and fnbpentangular; bafe narrowed; 
fides grooved ; avenues pulvinate'; crown central. Found 
frequently on the fandy coalts of the Netherlands': mouth 
oibicular. 
S6. Echinus faba : furface and bafe pulvinate; circum¬ 
ference obtufely oval ; fides hardly grooved ; avenues flat; 
crown a little prominent and central. The (hell is very 
thin, and white; without tubercles, but merely granu¬ 
lated ; the grains containing the roots of fin a 11 bridles 
■which arb inflead ot (pines. The vent and mouth are 
both underneath, and near together. On the upper fur¬ 
face is a five-rayed figure, full of little holes. One of 
the ('mailed kind ; not larger in general than a pea ; very 
feldom fo large as the egg of a (mall bird or a pigeon, 
which in fome refpetts it refembles, being always of an 
oval lhape, one end larger than the other. 
87. Echinus inequalis, the uneven fea-urchin: furface 
gibbous on the’fore-part, the hind-part flat and (loping; 
circumference oblong-oval and nearly pentangular ; bafe 
globular, and a little narrowed ; fides grooved ; avenues 
fubpulvinate; crown central; back unequal. 
88. Echinus rani'nus: furface globular and more (loping 
behind, circumference acutely oval; bafe globular; fides 
grooved; avenues fubpulvinate; crown central, Probably 
a variety of echinus minutus. 
89. Echinus bufonius: furface globular, circumference 
ovate, heart-ill aped, and fubtrigonal; bafe pulvinate ; fides 
(lightly grooved-; avenues pulvinate ; crown nearly cen¬ 
tral. Probably a variety of echinus minutus. 
III. Vent lateral ; month with pencilled tcntacula. 
Circular ; mouth central ; vent fquare. 90. Echinus 
.placenta: fubconic, with ten fpaces alternately narrower; 
avenues five, lax, flat, and gaping at the tip. Inhabits 
the Southern Ocean: a little convex and conoid ; the cir¬ 
cumference fomevv hat angular; the bafe flat; fpaces di¬ 
vided by an obtufely toothed vertical line; vent placed 
on the furface, and nearly marginal. 
Eleart-fliaped ; the crown grooved. 91. Echinus cor 
anguinum : above convex, with five impreflfed quadrifa- 
rioufly porous avenues, and five fpaces. Found hitherto 
in a foflile (late only ; and is probably the fame as echi¬ 
nus purpureus, in a petrified (late. 
92. Echinus lacunofus: ovate, gibbous, with five de- 
prefied avenues. Inhabits the Indian, Atlantic, and Eu¬ 
ropean, feas. Shell with a purplifh top ; (paces tubercu- 
late, in waved rows ; the lower fide (loaded and divided 
by two fmooth fpaces; fpines (hort, thick, mixed with 
long ones. The compartments are divided by deep fur¬ 
rows,- four of which are nat'row, but one is extremely 
broad, and almoft as deep as half the convexity of the 
apex ; it has a double row of pores at the bottom, and 
wrinkles on the (ides; it reaches round the (hell to the 
mouth ; oppofite this furrow, on the top, there is a long 
deep future, which goes to the vent in the circumference 
of the circle. The (hell is very thin ; furnilhed with 
rough dots or. grains, to which ihe fpines adhere. 
The following varieties are included by Gmelin under 
this (pecies. The fir If inhabits the Adriatic fea. It has 
a raifed lobe in the middle ; on each fide of which are 
four double lines, each confiding of two rows of pores: 
Von. VI. No, 345 . 
the longed lines are direfled towards the broaded extre¬ 
mity, and form a curve towards the (horter ones at the 
pointed end. The whole is fomewhat in the (hape of a 
heart, the large end being divided, the fmaller end con¬ 
tains the vent, and the mouth is underneath. The (hell 
is very thin and brittle. This is reprefented in the Echi¬ 
nus Plate II. fig. 6. The fpines are not thicker than 
horfehair, and about a quarter of an inch long ; when 
they are on the fnell is entirely covered with them, fo 
that neither furrow, future, nor aperture, can be feen. 
The fecond variety refembles the preceding ; but the 
fpines are long, and curved at the end^ like a fabre. Some 
have a fmaller fet of 'fpines, of a whitifli colour, inter¬ 
mixed with the brown ones, probably young ones to re¬ 
place thofe whic fall off. 
Heart-fhnped; the crown not grooved. 93. Echinus 
radians: avenues four, with imprefied flrite porous on 
each fide; crown with four pores; fpaces.ten, divided by 
a ferrate future in the middle, and arched trunfverfe fu¬ 
tures. Found hitherto only in a foflile (late. B :fe flat; 
mouth a little kidney-fhaped, and furrounded with a Cub- 
pentagonal flar of pores ; vent rounriifh, with three angles 
o - the margin ; avenues confiding of a row of pores placed 
dole together in pairs, each convergent on the crown. 
94. Echinus purpureus: avenues four, petal.fiiaped, 
lanceolate; larger tubercles placed in a zigzag manner; 
fpines acicular, incurved, white. Inhabits the North Seas: 
above convex ; the fides (loping ; fore-part with two pro¬ 
jections, hind-part truncate ; beneath flat; from the mouth 
to the vent a little convex and purple; very finely granu¬ 
late, and befet with fmall fubclavate bridles, and fpatu- 
late fpines feated on white tubercles ; near the vent a kid- 
ney-diaped dripe of minute white granulations, and fur- 
rounded with numerous white tubercles. 
95. Echinus pufilius : oval, with five avenues; vent re- 
mo'e. Inhabits the North Seas : very minute, and didinCt 
from echinus lacunofus; probably not of this divifion. 
96. Echinus complanatus : a little flattened each fide; 
fpaces and avenues ten, two of them placed in the fur¬ 
rows of the back. Found in a foflile date;- roundifh. 
97. Echinus fubglobulus: both ends convex, fubglo- 
bular, adulate ; avenues ten, with biporous Arias ; vent 
ovate. Found in a foflile date : granulate, with four pores 
on the crown ; fpaces divided by a longitudinal ferrate 
fu tore, and grooved with tranfverfe curved lines*, the 
pieces feven-lided; mouth fomewhat kid'ney-diaped, and 
furrounded with tubercles difpofed in a dellate form. 
98. Echinus ananchytis: oblong, heart-lhaped, and fub¬ 
conic; the bafe flatter; avenues and fpaces ten; mouth 
rounded and furrounded with an elevated margin; vent 
oval, and emarginate below. Found in a foflile date; the 
larger fpaces with (even angular pieces, lefler ones fix and 
five angled ; vent furrounded with an elevated band. 
99. Echinus bicordatus : with a double crown. Found 
hitherto in a petrified date only. 
100. Echinus carinatus: middle of the back carinate. 
Found in a foflile date ; refembles the lad, but is nar¬ 
rower behind: mouth kidney-fhaped ; vent obfolete. 
Ovate; the avenues grooved. 101. Echinus fpatagus: 
ovate, gibbous, with tour deprefled avenues; confiding 
of the following varieties : 1. Spotted. 2. Larger. 3. 
Knotty. 4. Of one colour. 5. Ovate. 6. Carinate. 7. 
Very large. Thefie inhabit mod feas: pale fulphur when 
frefh. Shell a little -heart-lhaped, gibbous at one end, 
and marked with a deep groove at the other; fpines (len¬ 
der, refembling bridles ; mod remarkably fragile. The 
fifth or ovate variety has the (hell thin and brittle. 
The mouth is not in the middle of the bafe, but rather 
towards the broad end ; the vent at the narrow end. The 
deprefled avenues or rays on the furface are each com- 
pofed of four rows of pores. In the middle, where 
the four rays unite, there are four holes forming a fquare, 
each big enough to admit the point of a pin. The tu¬ 
bercles and fpines are larger about the mouth and on the 
bafe. The (hell is made up of rhomboidal plates. 
3 O Ovate; 
