, 1891-05-06

the calcareous lining of its tunnel. The great
engineer Brunei affirmed hat the plan of Dor
ing to make the Thames Tunnel was suggested
to his mind by a study Of the working of the
Teredo.
Our definition excludes, Of course, the max
ed molluscs. Some allusiop to them could
scarcely be avoided if we adopt a wider eX-
PLANTATION of the word Conchology, and defn-
ed it as is lone in some text books, as the
science which treats of shells and the ami
mails which inhabit them. But that is really
Malacology-a much wider subject. The at
tempt to turn the one thing into the other
is nothing but a cowardly concession to
the taunt that the shell collectors employ
ment is as puerile as the stamp-c collectors.
Please note that it is not l who am speak
ing -contemptuously of the philatellist. Why
should not a man collect stamps, if he pleases ?
Only let him DO it without any mean ~pretence
of studying History or Geography. But Con
chology stands on a higher platform than Phi
latellical science by as much as Nature sur
passes Art, especially such Art as is required
for the manufacture of postage stamps. Con-
chology has charms Of her own apart from any
associations that can strictly speaking be call
ed scientific. Unless, indeed you start a new
Ology as a name for the science of the
Beautiful, and let it include everything which
delights the sense of sight-the delicate tint of
a petal, the pearly sheen of a she'll, the brilli-
ant flash from gem or star, OF the bend of n
bonny ee-bree." Conchology is not a mere
chapter in Biological science it holds high
rank in the Cult of the Beautiful. Neverthe-
less, as it is impossible to study a shell salts
factorily without reference to the structure
and habits of the creature to which it belongs,
we may freely admit, without prejudice, as
the lawyers would say, TO the position taken
up in orr definition, that the biological is a
most important and interesting part Of our
subject.
In the borderlanl between the shell bear
ing and naked Aioilusca, are some Cephalopods
with an internal hard support, a substitute for
a backbone, chalky in the Sopia or horny in
the Calmer or Squid. Here are specimens
shaped like pens from our Sea Cats"
In the same debateable land, or rather sea,
are the families Of the Semiphyllidiana and
Aplysiana, which have documentary horny caps
over their gills hidden in their m2ntles. OF
these creatures. the Sea-Hare is a good type. l
had several Of their shells, but they have
crumbled to dust owing to imperfect perscr-
walton. It will be easy to replace them, for
the sea-hares are abundant at the Fort. This
little animal, the Lagos Thalattios of Greek
and Sea-Iare also Of English boys, is called
by West Indian juveniles Sea-CoW', which GER
ItluIy 10 u HAoIO appropriate Hdil6' IL DedIs
no resemblance, Of course, to the monstrous
Manatis or Sea-Cow Of the depths of the Carrib-
bean; that is a horse, l mean a cow, Of quite
another colour and nature. Our little friend
at the Fort has four tentacles, two cylindrical
like horns and the other two broad like ears.
The back is high and the ventral foot prolong-
ed into a tail. When she is touched a milky
juice exudes which soon assumes a purplish
colour. The old naturalists and physicians
considered this juice to be horribly poisonous.
If a luckless small boy padding in the sea got
smeared with any of the sea-hare's milk, he
was Immediately carried off to the Doctor, who
promptly subjected him to a course Of heroic
antiphilogistics. Will the time come when
any of the awful and malefc microbes, which
destroy our bodies and harrow our souls to-day
will be r~elegated to the same limbo of fantas-
tic delusions ? Our ancestors laboured under
another extraordinary and most easily disprov-
ed hallucination about the Aplysia. They
held that the stain of its juice could never be
washed off whence its name from a and pluo.
Like the damned spot on Lady Macbeth's hand
it could not be eradicated but this as Mr..
Pears reminds us, was because his soap had
not yet been invented.
At last we may fairly open our genealogical
cabinet and take stock of its treasures. We
find that they vary to a degree in colouring,
size, texture, and shape.
These six specimens, taken almost at ran
dom, illustrate tho briliancy and diversity Of