The pugnacity shown by this individual specimen

J. G. T.  « The Caddis-Worm », Hardwicke’s Science-Gossip, Londres, 1 août 1867, p . 167.

The Caddis-Worm

Can any readers of the Science-Gossip explain the following unusual incident connected with the Caddis Worm ? Having caught a fine specimen, I introducted it into a can containing some young dace, intented as contributions to my aquarium ; whereupon the former having grasped the latter with its feet, gradually drew it within its case, until the head of the fish was completely hidden. Being desirous to fully comprehend the intention of the Caddis Worm, I watched the proceeding until the fish remained perfectly motionless : the worm then released its prisoner, who floating underneath dead, but after the lapse of ten or twelve minutes perfectly recovered itself.

On putting the same worm into my aquarium I saw it fix itselfat once on a « miller’s thumb » that was groping about at the bottom among the stones, and remain there until the infortunate fish rolled slowly on its side, and became quite stiff. Thinking it dead, I removed the Caddis Worm, and found my surmise was correct ; for though I left it for upwards of two hours, I found it gave not’ the slightest token of life. Having previously kept several of the above species in the same vessel without any hostility evinced from either the one the pugnacity shown by this individual specimen, and shall be glad if any one can offer an explanation of it.