OCR Text |
Show 78 HABITS OF WORMS. CrrAP. II. Petioles.-We will now turn to the petioles or foot-stalks of compound leaves, .after the leaflets have fallen off. Those from Clematis montana, which grew over a verandah, were dragged early in January in large numbers into the burrows on an adjoining gravelwalk, lawn, and flower-bed. These petioles vary from 2k to 4~ inches in length, are rigid and of nearly uniform thic]~ness, except close to the base where they thicken rather abruptly, being here about twice as thick as in any other part. The apex is somewhat pointed, but soon withers and is then easily broken off. Of these petioles, 314 were pulled out of burrows in the above specified sites; and it was found that 7 6 per cent. had been drawn in by their tips, and 24 per cent. by their bases; so that those drawn in by the tip were a little more than thrice as many as those drawn in by the base. Some of those extracted frorn the well-beaten gravel-walk were kept separate from the other~; and of these (59 in number) nearly five times as many had been drawn in by the · tip as by the base; whereas of those extracted from the lawn and flower-bed, where from the soil yielding more easily, less care would Le CIIAP. II. 'l'HEIR IN'l'ELLIGENCE. 79 necessary in plugging up the burrows, the proportion of those drawn in by the tip ( 130) to those drawn in by the base ( 48) was rather less than three to one. That these petioles had been dragged into the burrows for plugging them up, and not for food, was manifest, as neither end, as far as I could see, had been gnawed. As several petioles are used to plug up the same burrow, in one case as many as 10, and in another · case as many as 15, the worms may perhaps at first draw in a few by the thicker end so as to save labour; but afterwards a laro·e • • b maJonty are drawn in by the pointed end, in order to plug up the hole securely. The fallen petioles of our native ash-tree were next observed, and the rule with most objects, viz., that a large majority are dragged into the burrows by the more pointed end, had not here been followed ; and this fact much surprised me at first. These petioles vary in length from 5 to 8~ inches ; they are thick and Heshy towards the base, whence they taper gently towards the apex, which is a little enlarged and truncated where the terminal leaflet had been originally attached. Under some ash-trees growing in a grass-field, 229 |