In texture this is scarcely so stout as the shaft of a quill, nor so pale, but almost as transparent. As regards size, the terminal link or ‘button’ may be compared to the nail of a young child, the intermediate links gradually increasing with the growth of the snake to the nails of older children, and the largest link to that of a full-grown person. From the form of this rattle—an accurate copy of the original—we may infer that it grew rapidly at first, and that the snake was large during the development of the later links.
The next, reduced in size, is the rattle of a snake which had attained full growth, but from which the younger or earlier links with the terminal ‘button’ are gone.
Portion of a long rattle, much reduced in size.
Extending this specimen by imaginary converging lines, we form an idea of what its length might have been if perfect, probably about twenty joints, which is a not unusual number; but we perceive at once that a rattle, as we happen to see it, is no criterion of its age or its original form. Rarely is a snake seen with a long rattle perfect and entire. But whenever it gradually tapers and ends with the pointed terminal link, we may decide that that rattle has escaped injury from its earliest development.
In form it is not unsymmetrical, and in substance it is horny, like hair, nails, quills, and hardened skin, a sort of dense and corneous integument, yet less solid than horns and claws. The links, being only interlocked and yet elastic, can be easily separated, and are consequently easily injured. An animal treading on the rattle of a snake would cause a portion at least to be lost; or in being drawn among roots and entangled vegetation, a rattle might easily get damaged: the number of links can never, therefore, be an infallible clue to the age of the reptile.
Like hair, horns, nails, it is also subject to a caprice in growth, or to the vigour of the individual; at one time comparatively at a stand-still, at another growing rapidly; in one season gaining perhaps several links, in another season none.
Neither does the number of joints bear any relation to the casting of the skin, any more than the growth of hair or nails depends on the healing of a scar. The slough, cast more or less frequently, may leave the rattle intact, or a new link may appear at such a time. Dr. Cotton, of Tennessee, had a rattlesnake which shed its skin on an average twice a year, and he observed a new link to the rattle on each shedding. On the contrary, a rattlesnake at the London Zoological Gardens, and in the collection for about ten years, had never a rattle worth mentioning. Quite a young snake of only 15 inches when brought, it grew into a fine healthy specimen, fully five feet long, and yet had never more than what Americans call the button—not quite even that, but merely an abortive pretence of unhealthy growth, as if one or two links were consolidated. I watched that rattle for several years with much interest. Thus it was when my attention was first drawn towards it; and though it sometimes gave promise of growing, and once did indeed gain another link, it soon got broken off, and never attained more than three misshapen joints.
All there was of it!
From life.