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leaves had been pulled in； and the burrows were again well
protected。 These leaves could not be dragged into the burrows to
any depth； except by their bases； as a worm cannot seize hold of
the two needles at the same time； and if one alone were seized by
the apex； the other would be pressed against the ground and would
resist the entry of the seized one。 This was manifest in the above
mentioned two or three exceptional cases。 In order； therefore；
that worms should do their work well； they must drag pine…leaves
into their burrows by their bases； where the two needles are
conjoined。 But how they are guided in this work is a perplexing
question。
This difficulty led my son Francis and myself to observe worms in
confinement during several nights by the aid of a dim light； while
they dragged the leaves of the above named pines into their
burrows。 They moved the anterior extremities of their bodies about
the leaves； and on several occasions when they touched the sharp
end of a needle they withdrew suddenly as if pricked。 But I doubt
whether they were hurt； for they are indifferent to very sharp
objects； and will swallow even rose…thorns and small splinters of
glass。 It may also be doubted； whether the sharp ends of the
needles serve to tell them that this is the wrong end to seize； for
the points were cut off many leaves for a length of about one inch；
and fifty…seven of them thus treated were drawn into the burrows by
their bases； and not one by the cut…off ends。 The worms in
confinement often seized the needles near the middle and drew them
towards the mouths of their burrows； and one worm tried in a
senseless manner to drag them into the burrow by bending them。
They sometimes collected many more leaves over the mouths of their
burrows （as in the case formerly mentioned of lime…leaves） than
could enter them。 On other occasions； however； they behaved very
differently； for as soon as they touched the base of a pine…leaf；
this was seized； being sometimes completely engulfed in their
mouths； or a point very near the base was seized； and the leaf was
then quickly dragged or rather jerked into their burrows。 It
appeared both to my son and myself as if the worms instantly
perceived as soon as they had seized a leaf in the proper manner。
Nine such cases were observed； but in one of them the worm failed
to drag the leaf into its burrow； as it was entangled by other
leaves lying near。 In another case a leaf stood nearly upright
with the points of the needles partly inserted into a burrow； but
how placed there was not seen； and then the worm reared itself up
and seized the base； which was dragged into the mouth of the burrow
by bowing the whole leaf。 On the other hand； after a worm had
seized the base of a leaf； this was on two occasions relinquished
from some unknown motive。
As already remarked； the habit of plugging up the mouths of the
burrows with various objects； is no doubt instinctive in worms； and
a very young one； born in one of my pots； dragged for some little
distance a Scotch…fir leaf； one needle of which was as long and
almost as thick as its own body。 No species of pine is endemic in
this part of England； it is therefore incredible that the proper
manner of dragging pine…leaves into the burrows can be instinctive
with our worms。 But as the worms on which the above observations
were made； were dug up beneath or near some pines； which had been
planted there about forty years； it was desirable to prove that
their actions were not instinctive。 Accordingly； pine…leaves were
scattered on the ground in places far removed from any pine…tree；
and 90 of them were drawn into the burrows by their bases。 Only
two were drawn in by the tips of the needles； and these were not
real exceptions； as one was drawn in for a very short distance； and
the two needles of the other cohered。 Other pine…leaves were given
to worms kept in pots in a warm room； and here the result was
different； for out of 42 leaves drawn into the burrows； no less
than i6 were drawn in by the tips of the needles。 These worms；
however； worked in a careless or slovenly manner； for the leaves
were often drawn in to only a small depth； sometimes they were
merely heaped over the mouths of the burrows； and sometimes none
were drawn in。 I believe that this carelessness may be accounted
for either by the warmth of the air； or by its dampness； as the
pots were covered by glass plates； the worms consequently did not
care about plugging up their holes effectually。 Pots tenanted by
worms and covered with a net which allowed the free entrance of
air； were left out of doors for several nights； and now 72 leaves
were all properly drawn in by their bases。
It might perhaps be inferred from the facts as yet given； that
worms somehow gain a general notion of the shape or structure of
pine…leaves； and perceive that it is necessary for them to seize
the base where the two needles are conjoined。 But the following
cases make this more than doubtful。 The tips of a large number of
needles of P。 austriaca were cemented together with shell…lac
dissolved in alcohol； and were kept for some days； until； as I
believe； all odour or taste had been lost； and they were then
scattered on the ground where no pine…trees grew； near burrows from
which the plugging had been removed。 Such leaves could have been
drawn into the burrows with equal ease by either end； and judging
from analogy and more especially from the case presently to be
given of the petioles of Clematis montana； I expected that the apex
would have been preferred。 But the result was that out of 121
leaves with the tips cemented； which were drawn into burrows； 108
were drawn in by their bases； and only 13 by their tips。 Thinking
that the worms might possibly perceive and dislike the smell or
taste of the shell…lac； though this was very improbable； especially
after the leaves had been left out during several nights； the tips
of the needles of many leaves were tied together with fine thread。
Of leaves thus treated 150 were drawn into burrows123 by the base
and 27 by the tied tips； so that between four land five times as
many were drawn in by the base as by the tip。 It is possible that
the short cut…off ends of the thread with which they were tied； may
have tempted the worms to drag in a larger proportional number by
the tips than when cement was used。 Of the leaves with tied and
cemented tips taken together （271 in number） 85 per cent。 were
drawn in by the base and 15 per cent。 by the tips。 We may
therefore infer that it is not the divergence of the two needles
which leads worms in a state of nature almost invariably to drag
pine…leaves into their burrows by the base。 Nor can it be the
sharpness of the points of the needles which determines them； for；
as we have seen； many leaves with the points cut off were drawn in
by their bases。 We are thus led to conclude； that with pine…leaves
there must be something attractive to worms in the base；
notwithstanding that few ordinary leaves are drawn in by the base
or