212 . [Februury, 



the most intent on its food ; sometimes, while reposing within its case, it would lie 

 on the upper surface of a leaf, in which position it was not readily detected, the 

 assimilation being so perfect ; at other times, like its companion, it would be floating 

 concealed, its case being just in contact with the edge of a leaf or stem ; indeed, I found I 

 could not isolate either of them at such times in the clear space of water between 

 the leaves, for whenever I placed one there, as lightly as possible, it seemed drawn, 

 though gently, yet with an attraction irresistible, towards some part of the plant ; 

 and if one end of the case first touched it, the other end swung round till the side 

 of the case was in contact, when it would be still. 



Finding the water much sullied by the frass, I thought it necessary to have it 

 changed every second day, and each time this operation occurred, the larvaj and their 

 food were transferred, for a few minutes, from the large china bowl in which they 

 were kept to a saucer of water, and while here it happened, on three occasions, that 

 pellets of frass were ejected, with some force, out of the water, to the distance of 

 eight inches beyond the saucer, on the table : its propulsion seemed frequently to be 

 in an upward dii'cction, as I constantly noticed, latterly, a large proportion of frass 

 adhering to the side of the bowl two inches or more above the water. 



After feeding well for ten days, during which time all the five leaves of the 

 plant sent with them had become much ravaged and reduced to fragments, to my 

 great satisfaction, the larviB appeared on the 16th of the month to have ceased 

 feeding ; and towards evening I was greatly surprised to see the smaller larva had 

 abandoned its case, and was crawling naked over the remains of its food-plant, its 

 colour a little faded ; on the morning of the 17th I found it half out of the water, 

 on the side of the bowl ; in the afternoon I saw, with much perplexity, the larger 

 larva had also left its case, and was crawling about through the water in a forlorn 

 condition, and much paler than before. I now had great anxiety for their ultimate 

 fate, as their behaviour did not seem to agree with their alleged habit of pupating 

 within their cases, which were still as fresh-looking as at first ; so, with a faint hope 

 of their spinning up amongst the debris of their food, I left them for the night. 

 The next moi'ning, seeing both larvae out of the water, and looking very miserable, 

 it struck me they were seeking some other kind of plant to make up in, and I 

 supplied some Callitriche verna and Helosciaditim nodiflorum, but on neither of 

 these plants would they stay, and I then tried some pieces of Sparganium ramosum, 

 on wliich they crawled about and lingered some time, which induced me to obtain 

 several longer pieces, and to stand them upright, with the lower ends in water, 

 within a glass globe, and, after placing the larva; there, to tie over a piece of muslin 

 at the top, lest they might wander away ; this arrangement proved successful ; the 

 burr-reeds were now it position as they would be naturally growing out of water, 

 and I had the great pleasure and relief of seeing, within a minute, the larger larva 

 creep up about an inch or so above the water level, between two pieces of the Spar- 

 ganium, and immediately begin to spin them together ; the smaller larva also soon 

 found out two other pieces suitable, and began to spin them together in the same 

 manner, and at the same distance above the water; and I watched their proceedings 

 as long as tiieir heads could be seen in motion, sometimes upwards from side to side, 

 and then below in the same way, until the surfaces were closed up entirely. I let 

 them remain imtil a week had elapsed, when, seeing the Sparganium begin to look 

 bad at the bottom, I cub the pieces shorter, and st»od thorn on some dry moss in a 

 pot covered with gauze. 



