Pleasure from a few caddis larvae

M. Pope, « Caddis-Worms », Science Gossip, Londres, mai 1866, pp. 109-110.

About this time last year I derived so much pleasure from a few caddis larvae, that I should like to induce any who have never tried such experiments to do se, promising them a lasting fund of enjoyment. In the « Scientific Summary » of Popular Science Review for January, 1864, was an account of experiments made by Miss Smee in regard to the building capacities of the caddis-worm. Afterwards I read an article by the same lady in the Intellectual Observer, in which she gave a most interesting history of her experiments. If Miss Smee could force these little creatures to build of such a variety of things , why should not I ? Already I had dozens of the larvae in my aquarium, and following Miss Smee’s directions, I broke different coloured glasses into tiny bits, also pearl and gold beads, fragments of coral and shell com, placing them in saucers of water ; then the larva had to be turned off its case. This can only be done by gently irritating the tail with a needle or pin, as no force will induce it to leave its home with life, the last segment being provided with two strong books, with which they cling so tenaciously to the case, that they will suffer themselves to be pulled in two rather than release their hold. These hooks can be easily seen with a pock lens. Very soon after the homeless larva has been placed among the bits of glass, &c., it will commence to construct a new case. I never remember experiencing greater delight than I did in watching the «  water-maggots » adapting substances so novel to their own requirements cementing each fragment firmly and no matter how diverse the size and shape of the materials used, always keepung the inner surface perfectly smooth and even. The caddises are not long in building, and the addition of a few purple green, or bine glass cases, with here and there a shining bit of gold or pearl bead, makes a pleasing variety in the aquarium. I had one fine larva last spring, which every movement of its body could be plainly seen. The first day i twas placed in the aquarium it occasioned quite a commotion amongst the pugnacious sticklebacks, which by the way, are scarcely more pugnacious than caddises themselves. The deception was so perfect that they mistook it for an uncased grub, and with mouths watering in anticipation of the delicious morsel «  so near and yet so far, » dashed against the transparent armour in dire indignation. After a little while they ceased all attacks, I suppose I must say from instinct, though I am far more inclined to call it reason. Caddis-worms can be obtained from almost every river and stream, and as they always build in accordance with the specific gravity of the water, the larger cases will be found in the bed of a deep or swiftly flowing river. These are generally constructed of small pebbles and Planorbis shells (not unfrequently with living inmates), while in shallow streams, or crawling among the river-weeds, may be found those which construct their homes entirely of vegetable substances.  I think the caddises might be classed into vegetarians and carnivorians, homoepaths and allopaths, for some live entirely on a vegetable diet, others prefer meat in large quantities, while some build for days, and as far as I can see, never eat at all. The carnivorians are decidedly preferable for architectural purposes ; they seem stronger and more active ; while the vegetarians use the weeds given them to allay their hunger in building a fresh case. When dredging for caddises, I sometimes transfer from the net to the can the close-uo cases which are every-where to be met with.