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that alone which proves possible or the most easy； but to act in
this manner and to try different methods makes a near approach to
intelligence。
In the first place 227 withered leaves of various kinds； mostly of
English plants； were pulled out of worm…burrows in several places。
Of these； 181 had been drawn into the burrows by or near their
tips； so that the foot…stalk projected nearly upright from the
mouth of the burrow； 20 had been drawn in by their bases； and in
this case the tips projected from the burrows； and 26 had been
seized near the middle； so that these had been drawn in
transversely and were much crumpled。 Therefore 80 per cent。
（always using the nearest whole number） had been drawn in by the
tip； 9 per cent。 by the base or foot…stalk； and 11 per cent。
transversely or by the middle。 This alone is almost sufficient to
show that chance does not determine the manner in which leaves are
dragged into the burrows。
Of the above 227 leaves； 70 consisted of the fallen leaves of the
common lime…tree； which is almost certainly not a native of
England。 These leaves are much acuminated towards the tip； and are
very broad at the base with a well…developed foot…stalk。 They are
thin and quite flexible when half…withered。 Of the 70； 79 per
cent。 had been drawn in by or near the tip； 4 per cent。 by or near
the base； and 17 per cent。 transversely or by the middle。 These
proportions agree very closely； as far as the tip is concerned；
with those before given。 But the percentage drawn in by the base
is smaller； which may be attributed to the breadth of the basal
part of the blade。 We here； also； see that the presence of a foot…
stalk； which it might have been expected would have tempted the
worms as a convenient handle； has little or no influence in
determining the manner in which lime leaves are dragged into the
burrows。 The considerable proportion； viz。； 17 per cent。； drawn in
more or less transversely depends no doubt on the flexibility of
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