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Show 76 HABITS OF WORMS. CnAP. II. 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 sei?.e 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 daysJ until, as I believe, all odour or taste had been lor:;t; and they were then scattered on the ground where no pine-treBs grew, ncar burrows from which the plugging had been removed. Such leaves could have been drawn into the bnrrows with equal ease by either end ; and judging from analogy and more especially from the case presently to Lc 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 La es, and only 13 by tl1eir tips. Thinkjng that the worms might possibly perceive and dislike the smell or taste of the shell-lac, though this was very improbable, especially after the CHAP. II. TTIEIR INTELLIGENCE. 77 leaves had been left out during several nights, t~1e tips of the needles of many leaves were tied together with fine thread. Of leaves thus treated 150 were drawn into burrows- 123 by the base and 27 by the tied tips; so that bet.ween four and 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 t~mpted 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 ( 2 71 in n urn ber) 85 per cent. were drawn in by the base and ~5 per cent. by the tips. We may therefore lnfer 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 determin~s 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 Le somethin; attractive to worms in the base, notwithstanJing that few ordinary leaves are drawn in by the base or foot-stalk. |