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Show 82 HABITS OF WORMS. CnAP. II. possible to ascertain whether wonns had gnawed the bases, though this is in i~self probable. Out of 121 petioles extracted from burrows early in February, 68 were embedded by the base, and 53 by the apex. On February 5 all the petioles which had ?e~n drawn into the burrows beneath a Robinia, were pulled up ; and after an interval ~f eleven days, 35 petioles had been again dragged in, 19 by the base, and 16 by the apex. Taking these two lots together, 56 per cent. were drawn in by tbe base, and 44. per cent. by the apex. As all the softer parts had long ago rotted off, we may feel sure, especially in the latter case, that none had been drawn in as food. At this season, therefore, worms drag these petioles into their burrows indifferently by either end, a slight preference being given to tho base. This latter fact may be accounted for by the difficulty of plugging up a burrow with objects so extremely thin as are the upper ends. In support of this view, it may be stated that out of the lG petioles which had been <lrawn in by their upper ends, the more attenuated terminal portion of 7 had been previously broken off by some accident. CHAP. II. 'l'JIEIR INTELLIGENCE. 83 Triangles of paper.-Elongated triangles we~e cut out of moderately stiff writing-paper, whiCh was rub bed with raw fat on both sides s.o as to prevent their becoming excessive!; hmp when exposed at night to rain and dew The sides of all the triano-les were thrc~ inches in length, with the bc'tses of 120 one inch, and of the other 183 half an inch in length. These latter triangles were very narrow or much acuminated.* As a check on the observations presently to be o-iven similar triangles in a damp state were ~eized by a very narrow pair of pincers at different points and at all inclinations with reference to the margins, and wore then drawn into a short tube of the diameter of a wormburrow. If seized by the apex, the triangle was drawn straight into the tube, with its margins infolded; if seized at some little distance frorn the apex, for instance at half an inch, this much was doubleJ back within the tube. So it was with the base and ba al angles,. though in this case the triancrles ffi . 0 o ered, as might have been expected, much b ,.. In these narrow triangles the apical anrrlo is 9° 34' and th, 19asoa l1 0an' O0 'lods 8h5 ° 13·' · I n th e b roa d or tn.a ngl"o' s tho apical' 'a rwlc ise au i e basal angles 80° 25'. b G 2 |