42
ANATINID/E.
rib indistinct : hinge-line obtusely angular : Mnrfe-plate thick
and strong: ossicle semilunar, slightly attached, and consequently often lost in dead specimens: inside crcameolour, somewhat glossy and nacreous ; edges blunt : scars large and well
defined. L. 0-G. B. 0-8.
Var. tnincata.
Shell oblong ; front margin straight ; posterior margin abruptly truncated. Anatina trmicata, Turton,
Dith. p. 46, t. 4. f. 6.
Habitat : From Guernsey to Unst^ in crevices of
rocks and old oyster-shells^ between 5 and 35 f., as well
as occasionally buried in tufts of Corallina officinalis at
low water; local, but widely diffused. The variety is
from Exmouth, Tenby, and Cork. Fossil in the Coralline Crag (S. Wood); Palermo (Philippi). Foreign
range : Finmark to the Cattegat, 3-40 f. (Loven and
others) ; north of France (De Gerville and others) ;
Provence (Martin) ; Algeria (Deshayes and Weinkauff)
This is the smallest British Thracia-, and its habitat
is diflPerent from that of its congeners. It may also be
known by its irregularly oval shape, its less angular
outline, uniform granulation, and comparatively large
cartilage-pit.
The young are triangular, and somewhat
resemble a Montacuta. A full-grown specimen taken
from a narrow chink in a piece of limestone well exemplifies the mode in which shells are constructed. Part
of the left valve had been crushed, apparently by accidental pressure ; and in order to repair the damage, an
inner layer was formed by exudation from the mantle,
to which the broken fragments were cemented and still
adhere.
The distorted growth of this species shows
that it does not excavate the holes in which it lives.
It sometimes appropriates the labours of other animals,
but never unjustly or consciously, like a plagiarist.
The original and short-lived fabricators of the dwellings
subsequently occupied by the Thracia are beyond the
ANATINID/E.
rib indistinct : hinge-line obtusely angular : Mnrfe-plate thick
and strong: ossicle semilunar, slightly attached, and consequently often lost in dead specimens: inside crcameolour, somewhat glossy and nacreous ; edges blunt : scars large and well
defined. L. 0-G. B. 0-8.
Var. tnincata.
Shell oblong ; front margin straight ; posterior margin abruptly truncated. Anatina trmicata, Turton,
Dith. p. 46, t. 4. f. 6.
Habitat : From Guernsey to Unst^ in crevices of
rocks and old oyster-shells^ between 5 and 35 f., as well
as occasionally buried in tufts of Corallina officinalis at
low water; local, but widely diffused. The variety is
from Exmouth, Tenby, and Cork. Fossil in the Coralline Crag (S. Wood); Palermo (Philippi). Foreign
range : Finmark to the Cattegat, 3-40 f. (Loven and
others) ; north of France (De Gerville and others) ;
Provence (Martin) ; Algeria (Deshayes and Weinkauff)
This is the smallest British Thracia-, and its habitat
is diflPerent from that of its congeners. It may also be
known by its irregularly oval shape, its less angular
outline, uniform granulation, and comparatively large
cartilage-pit.
The young are triangular, and somewhat
resemble a Montacuta. A full-grown specimen taken
from a narrow chink in a piece of limestone well exemplifies the mode in which shells are constructed. Part
of the left valve had been crushed, apparently by accidental pressure ; and in order to repair the damage, an
inner layer was formed by exudation from the mantle,
to which the broken fragments were cemented and still
adhere.
The distorted growth of this species shows
that it does not excavate the holes in which it lives.
It sometimes appropriates the labours of other animals,
but never unjustly or consciously, like a plagiarist.
The original and short-lived fabricators of the dwellings
subsequently occupied by the Thracia are beyond the