S.H. Chubb, « Master Masons and Builders », House & Garden, New York, McBride, Nast & Co., juin 1915, pp. 424-425.
Nearly everyone, who is in the habit of drinking at a spring in the primitive fashion with neither cup nor glass, has discovered those curious little cylinders, crawling, or rather being dragged, about on the bottom by their occupants and builders, the caddis worms, or, to speak more correctly, the larvae of the caddis fly. This litle creature has solved the landlord problem. The monthly demand comes nos his door !
While most of these structures are of the cylindrical school of architecture, there is a great diversity of treatment displayed by the various species, although the available material has much to do with the appearance of the finished dwelling. Almost anything which can be found at the bottom of streams and ponds may be used. Bits of sticks, tiny seeds, pieces of leaves, grains of sand or small stones are gathered and fastened together with silk-like threads of the builder’s own make. The case is also nicely lined with this material, which is spun very much as a silkworm or caterpillar spins its cocoon. The separate threads can be distinguished only when magnified about ten times.
The larva is a soft-bodied little grub, too empting to escape the sharp eyes of smalll fishes, were it not for his strange covering. When there seems to be no danger near, the head and legs of the hermit protude at the open end of the cymlinder and he will crawl about leisurely, dragging his home with him. At the extrême posterior end of the body there are two hooks with which he hold tenaciously to the Inside of the case, and will refuse to be extracte even at peril of being pulled in two. An attack from the rear, however, is so unusual an experience that it takes him quite by surprise. Should you wish to examine him more thoroughly, take a pine-needle or fine grass stem and thrust it gently into the very small opening at the posterior end of the case, and the probability is he will make a hasty advance out the other end, but will soon dive in again head first and then turn round at his leisure.
On one occasion, having a number of caddis larvae under close observation. I found that by some chance one caddis had been divested of his covering. Instead of adopting the usual course of diligently setting to work to repair the loss, this individual became alarmed and quite demoralized, broke into the back door of one of his neighbors, driving him out the front way. The rightful owner turned round and faced the enemy, but could not prevail. After some manoeuvring he discovered the breach in the rear and drove out the intruder, who then repeated his strategic move. This most unprofitable « merry- go- round » continued for some time without any evidence of merriment. The final outcome was the hasty building of a new retreat, whether by the interloper or the dispossessed I am, unfortunately, not able to say…/…A much more perfectly constructed variety of case is made of tiny stones of various shapes, sizes and colors, nicely fitted together, forming a most beautiful little mosaic. The material is not collected at random, but stones are selected which will give the finished structure a comparatively even surface both Inside and out. The posterior end of the case is covered by a single stone, leaving one or more minute opening around its edge for the circulation of water. This is one of the most beautiful varieties found in the Catskills.
For six hundred year or more the mosaic of the Novicella at St. Peter’s in Rome has excited wonder and admiration, and yet it is almost appalling to reflect that these lowly little creatures were diligently gathering stones, hewn out by Nature’s Tools, and fitting them into their mosaic designs with marvelous skill thousands of years before the foundations of St. Peter’s were laid : while the arch-stones were resting in their geological beds.
A variety somewhat similar to that just described is composed of fine grains of sand, slightly curved, and tapering toward the rear.
An interesting, though not particulary beautiful shelter, appears at first sight to be merely a little pile of stones. It is however, designed with some care, for under this dome is a living-room with a floor of fine grains of sand through which there is an opening, allowing the inmate to feed upon minute vegetable matter without even his head appearing from under cover. This species, unlike the others mentionned, prefers the most swiftly-running places in a stony brook, where they may be found by hundred clinging to the sloping surfaces of rocks. They move about very liitle. After the larva has built his tent over him he proceeds to drag it about until a suitable pitching site is found, where he makes fast and remains as long as pastures are green.
Nature, with all her endless resources, now and then seems to fall short of designs, so that we find apparent imitations or repetitions or accidental ressemblance between creatures of very widely separated stations in Nature’s scale. For instance, the armadillo with its horny shell is very suggestive of a turtle, the former belonging to the great order of mammals and the latter to the reptiles. Stranger still is the pangolin of Africa with its scaly covering suggesting a pine-cone walking on four legs. The caddis, it would seem, also feels this lack of originality ; for once, while scanning the sand very closely at the edge of a Catskill Mountain brook, I found a number of what appeared to be tiny snail-shells three-sixteenths of an inch or less in diameter. Beginning at the apex, though much too small to be seen by the naked eye, the little spirals gradually widened in perfect curves, and curiously enough, winding in the same direction as the common garden snail. With a magnifying glass it could be seen that they were made of the finest grains of sand fitted together and forming this wonderful copy of a minute snail shell.
Now these little structures had not simply grown like a flower in a mysterious manner which we hardly attempt to understand, but had been manufactured with mechanical skill which we would suppose must take years of experience to acquire. Yet each little caddis, about as soon as he was hatched, set to work to build himself this marvelous home without ever serving a day of apprenticeship. How is it done ? We say by instinct ; yet this takes nothing from the wonder of it nor offers any very satisfactory explanation.
In the beautiful little stream flowing through Sleepy Hollow, within a stone’s throw of the old Church which was made famous by Washington Irving, we found hundreds of little creatures, almost microscopic in dimensions, which had saved time and labory by crawling into any little bit of hollow stem available, but in compliance with the usual caddis habit, had loosely attached a few tiny fragments to the outer surface of their improvised cylinders.
How it must have frightened the wary little creatures when those hoofs went thundering across the bridge over their heads in the dead of night, and they heard the hollow thud of that grewsome pumpkin as it was precipitated upon the cranium of poor Ichabol !
But a New Yorker need not go to the Catskill or even to Sleepy Hollow to find caddis worms. Within sound of Broadway trafic and in sight of the Subway trains, above where they emerge from the tunnel, the little stonemasons may be found in abundance. In a spot no larger than a barrelhead fifty of one of the commoner varieties were counted, and it was here that we found one of the most interesting species.
For lack of something better, let us compare it with a well-rounded oyster shell with the hollow side down and a cornucopia-shaped pocket on the under side. This little shell, only one-half of an inch in length and composed of the grains of sand from the bottom, over which it moves, is almost invisible. The inmate is particularly well protected, too as he enjoys considerable freedom under hos own canopy, coming out of the pocket nearly his full length and reaching about with-out appearing beyond the edge of the shell. When undisturbed he is much more active than any psecies. I have observed, every move being quick and energetic.
One individual, kept for a time under close observation, became sufficiently domesticated to relish little particles of lettuce leaves, but it must be confessed here that finally he was cruelly robbed of his house. It was needed for the camera. I thought he could probably build another ; certainly I could not, but I did furnish him with the very best of material, nice fine sand composed chiefly of water-worn grains of quartz, somewhat transparent so that he might reveal his methods of constructing a home. The work was soon started by his burying himself just beneath the surface of the sand. With the microscope he could be seen through the quartz diligently « sewing » those grains together which immediately surrounded his head, thus forming a ring. Other grains were added to the forward edge of this ring, forming a slender cone, enlarging as he progressed. Soon he had come quite to the surface of the sand, so that the work could be watched more perfectly. The posterior end of the body now protruded only a little beyond the small end of the cone. Then the edges of the shell were begun, extending out on opposite sides of the cone and gradually widening until the pocket was completed. The curve of the shell was now continued forward and laterally, the workman reaching out for a grain of sand, then rolling over on his back to place it in position over his head.
The work was carried on with great rapidity. Every grain seemed to be handled in nervous haste, with only an occasional pause, apparently for rest. Through the microscope each grain of sand, which, when compared with the worker, seemed like a stone or great rock, was picked up between the two front feet and tried in a certain space, turned over rapidly once or twice, and then end for end, until it could be made to fit. Frequently, when a fit was found quite impossible, not the stone but the space, would be discarded for another. The stone finally fitted, was then made fast with a few silk threads, and all this in a few seconds. The time spent in building this structure, which was not so large one of the two illustrated, it may be of interest to know, is made up of no less than fourteen hundred stones all fitted into place one by one.
As a designer, I should say this species is among the most accomplished, but in workmanship not equal to the simple stone cylinder maker. In the latter the stones are fitted much more perfectly and bound together with hundreds of silk threads, making a very strong structure, whereas the « oyster-shell » variety is so delicate that it must be handled with the greatest care.
The larva is surprisingly small, as compared with the shell, being less than one-third its length and quite slender. Even the inner pocket is so spacious as to give the inmate almost room enough to run about, while with most species house and tenant make a pretty close fit.
How strange that there should be such a diversity of taste shown among these kinsfolk and what a world of craftsmanship is to be found within these narrow walls ! Probably there are no labor troubles among these workers ; every man his own employer ; every shop a closed shop. Ut what an example of primitive indivualism, walling one’s self into a stone cell, reaching out to take what hem ay and then retiring, whith no anxiety for the rest of his kind. But how characteristic of primitive nature even to the human race ! The chinese had made a great advance when, instead of sealing themselves up as individuals or even a small families or cities, they included a nation within the protection of their great wall. Since then we have learned that no nation liveth unto itself, and, indeed, at présent we painfully realize that no nations can slay and destroy each other without inflicting a blow upon the whole human race. Yet, in the face of the greatest setback of history, and in spite of the Bernhardi philosophy, when we look back to earlier civilizations, as in the time of Nero, we can say that altruism has slowly advanced and humanity will begin to climb once more as the present horrors susbside. Though our generation may not see it, the day will come when great armaments shall be no more, and to those who look back upon to-day encircling fortresse wull seem as primitive as the cell of the caddis.
There are many other species of the caddis displaying as many different forms of protective covering. One, for instance builds a stationary shelter from which the sallies forth a very short distance in search of food but turns homeward upon the slightest alarm.