R.H. Busk, « Animated Horsehairs » Notes and Queries a Medium of Entercommunication for Literary Men, General Readers, etc., 26 mars, Londres, 1887, p. 249-250.

About the caddis-worm I beg to thank him for his information, as the matter is quite outside my own line of study. I received the (as it appears wrong) instruction along with some specimen which were obtained for me out of a mountain stream near where I was living at one tinn in Piedmont, where the diversified colouring ; of the grit and pebbles made them particulary beautiful. The creatures inside them had the appearance of large pale yellow caterpillars (some already having their wings and some not). How the Caterpillar-like creature could construct the cylinder round itself, elastic spring-hinged door and all complete, while yet remaining quite loose and free inside it I confess entirely passes my comprehension ; but if it is so, the earlier illustration I named (p.25) suppled a better analogy.