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these half…decayed leaves。 The fact of so many having been drawn
in by the middle； and of some few having been drawn in by the base；
renders it improbable that the worms first tried to draw in most of
the leaves by one or both of these methods； and that they
afterwards drew in 79 per cent。 by their tips； for it is clear that
they would not have failed in drawing them in by the base or
middle。
The leaves of a foreign plant were next searched for； the blades of
which were not more pointed towards the apex than towards the base。
This proved to be the case with those of a laburnum （a hybrid
between Cytisus alpinus and laburnum） for on doubling the terminal
over the basal half； they generally fitted exactly； and when there
was any difference； the basal half was a little the narrower。 It
might； therefore； have been expected that an almost equal number of
these leaves would have been drawn in by the tip and base； or a
slight excess in favour of the latter。 But of 73 leaves （not
included in the first lot of 227） pulled out of worm…burrows； 63
per cent。 had been drawn in by the tip； 27 per cent。 by the base；
and 10 per cent。 transversely。 We here see that a far larger
proportion； viz。； 27 per cent。 were drawn in by the base than in
the case of lime leaves； the blades of which are very broad at the
base； and of which only 4 per cent。 had thus been drawn in。 We may
perhaps account for the fact of a still larger proportion of the
laburnum leaves not having been drawn in by the base； by worms
having acquired the habit of generally drawing in leaves by their
tips and thus avoiding the foot…stalk。 For the basal margin of the
blade in many kinds of leaves forms a large angle with the foot…
stalk； and if such a leaf were drawn in by the foot…stalk； the
basal margin would come abruptly into contact with the ground on
each side of the burrow； and would render the drawing in of the
leaf very difficult。
Nevertheless worms break through their habit of avoiding the foot…
stalk； if this part offers them the most convenient means for
drawing leaves into their burrows。 The leaves of the endless
hybridised varieties of the Rhododendron vary much in shape； some
are narrowest towards the base and others towards the apex。 After
they have fallen off； the blade on each side of the midrib often
becomes curled up while drying； sometimes along the whole length；
sometimes chiefly at the base； sometimes towards the apex。 Out of
28 fallen leaves on one bed of peat in my garden； no less than 23
were narrower in the basal quarter than in the terminal quarter of
their length； and this narrowness was chiefly due to the curling in
of the margins。 Out of 36 fallen leaves on another bed； in which
different varieties of the Rhododendron grew； only 17 were narrower
towards the base than towards the apex。 My son William； who first
called my attention to this case； picked up 237 fallen leaves in
his garden （where the Rhododendron grows in the natural soil） and
of these 65 per cent。 could have been drawn by worms into their
burrows more easily by the base or foot…stalk than by the tip； and
this was partly due to the shape of the leaf and in a less degree
to the curling in of the margins： 27 per cent。 could have been
drawn in more easily by the tip than by the base： and 8 per cent。
with about equal ease by either end。 The shape of a fallen leaf
ought to be judged of before one end has been drawn into a burrow；
for after this has happened； the free end； whether it be the base
or apex； will dry more quickly than the end imbedded in the damp
ground； and the exposed margins of the free end will consequently
tend to become more curled inwards than they were when the leaf was
first seized by the worm。 My son found 91 leaves which had been
dragged by worms into their burrows； though not to a great depth；
of these 66 per cent。 had been drawn in by the base or foot…stalk；
and 34 per cent； by the tip。 In this case； therefore； the worms
judged with a considerable degree of correctness how best to draw
the withered leaves of this foreign plant into their burrows；
notwithstanding that they had to depart from their usual habit of
avoiding the foot…stalk。
On the gravel…walks in my garden a very large number of leaves of
three species of Pinus （P。 austriaca； nigricans and sylvestris） are
regularly drawn into the mouths of worm burrows。 These leaves
consist of two so…called needles； which are of considerable length
in the two first and short in the last named species； and are
united to a common base； and it is by this part that they are
almost invariably drawn into the burrows。 I have seen only two or
at most three exceptions to this rule with worms in a state of
nature。 As the sharply pointed needles diverge a little； and as
several leaves are drawn into the same burrow； each tuft forms a
perfect chevaux de frise。 On two occasions many of these tufts
were pulled up in the evening； but by the following morning fresh
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 worm