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Show 86 IIABITS OF WORMS. CnAP. II. been dracro·ed into the burrows by the "basal ~v . than by the apical part; hut we shall im-mediately see how different was the result. Triangles of the above specified sizes were scattered on the ground in many places and on n1any successive nights near worm-burrows, from which the leaves, petioles, twigs, &c., with which they had been plugged, were rmuoved. .Altogether 303 triangles were drawn by worms into their burrows : 12 others were drawn in by both ends, but as it was impossible to judge by which end they had been first seized, these are excluded. Of the 303, 62 per cent. had been drawn in by the apex (using this term for all drawn in by the apical part, one inch in length) ; 1 5 per cent. by the middle; and 23 per cent. by the basal part. If they had been drawn indifferently by any point, the proportion for the apical, middle and basal parts would have been 33· 3 per cent. for each; but, as we have just seen, it might have been expected that a much larger proportion would have been drawn in by the basal than by any other part. .As the case stands, nearly three times as many were drawn in by the apex as by the base. If we CHAP. II. 'l'IIEIR INTELLIGENCE. 87 consider the broad triangles by themsclve , 59 per cent. were drawn in by the apex, 25 per cent. by the middle, and 1.6 per cent. 1Jy the base. Of the narrow triangles, 65 per cent. were drawn in by the apex, 14 per cent. by the middle, and 21 per cent. by the base; so that here those drawn in by the apex were more than 3 times as many as those drawn in by the base. We may therefore conclude that the rnanner in which the triano-les are d . b rawn Into the burrows is not a matter of chance. In eight cases, two triangles had been drawn into the same burrow, and in seven of these cases, one had been drawn in by the apex and the other by the base. This again indicates that the result is not determined by chance. Worms appear sometimes to revolve in the act of drawing in the triangles, for five out of th~ whole lot had been wound into an irregular spire round the inside of the burrow. Worms ~ept in. a warm room drew 63 triangles Into their burrows; but, as in the case of the pine-leaves, they worked in a rather careless manner, for only 44 per cent. were drawn in by the apex, 22 per cent. by the middle, and |