THE HAMILTON ASSOCIATION. 51 



them, are visible the water snails, amongst which is conspicuous the 

 Planorbis, or Coil Shell, a representative left us of the Ammonite, one 

 of the most universal fossils of the secondary rocks ; shells whose pro- 

 portions have dwindled down from their colossal size in days of yore, 

 when their circumference equalled that of a wheel, to that of an 

 ordinary small coin, contrasting in their diminution the present pigmy 

 race of man with his predecessors. Here we see the dragon 

 fly disporting on its gauzy wings, itself glittering with blue and 

 green flashing back the sunshine, now hovering poised above the 

 surface of the pool as if desirous of telling its kindred larvae, who 

 still remain below, and from one of which it lately sprung, the glorious 

 beauty hereafter awaiting them when their transformation takes 

 place ; but the watery element defies the advance of insect life, and 

 between them there is a great gulf fixed. Fancy may lead us to 

 picture to ourselves the Grub, preparatory to bursting his prison 

 house by the water side and rising on glittering wings into the sum- 

 mer air, promising tidings to its fellows of the state it is about to 

 enter, and the longings of those left behind to hear something of that 

 state, dimly fancied by them, but unknown. We could fancy him 

 returning amidst the transports of his wildest flights, ever and anon, 

 to the precincts of that watery world which had once been the only 

 world to him ; and thus divided, yet near, parted, yet united by love, 

 he hovers about the barrier that lies between them, darting over the 

 crystal water in the rapture of his new life. 



Let us scoop up a handful of water from the pond, and carefully 

 examine it. Our naturalist will tell us that there is in it a creature 

 with neither arms nor legs, properly so called, but which catches 

 animals more lively than itself, and twice its own size ; with no eyes, 

 yet loving the sunshine : whose stomach can be turned inside out, 

 apparently without hurting it, and which, if cut in two, will not die, 

 but each part grow into a perfect creature. To inexperienced eyes 

 it looks like a tiny piece of green sewing silk, about a quarter of an 

 inch long, and a little untwisted at one end. This, however, is really 

 a set of delicate limbs placed round the thicker end of the slender 

 body of the little Hydra (for such is the name it goes by). These 

 tentacles, or feelers, float in the water like fairy fishing lines. Little 

 creatures, invisible to our unaided sight, that have been frisking 

 round full of life and activity, are seized by them, and one tentacle 



