48 



In June arid July of 1880 this desire, as regards myself, was, in a measure, gratified. 

 I had the pleasure of watching the insect through its changes, from its larval to its 

 pupal condition. The circumstances were these : — 



On the 12th of June a lad brought me a strange creature which he had captured 

 as it was crawling up the bank of the Yamaska River. (See a, Fig. 7.) It was four 

 inches long, and about half an inch broad. Its colour was dark sepia. It had twelve 

 segments beside the head. The first three of these were evidently thoracic, for the legs 

 were attached to them, a pair to a segment. Each of the nine abdominal segments 

 carried two remarkable appendages, one on either side, inclosing, I suppose, the branchiae 

 or gills. They were about a quarter of an inch in length, and gave the insect a fringed 

 appearance. On the last segment they approached and over lapped the aual setae. The 

 square head of the insect was suggestive : and I said, " This must be the larva of the 

 Horned Corydilis," and I took measures for its safety. 



I procured a large flowerpot and half tilled it with earth. In this earth I sank to the 

 brim, a saucer full of water. I then put in the larva, and covered the pot with a pane of 

 glass. The creature buried itself on the second day ; I left it undisturbed for a week and 

 then thought I would remove the earth carefully until I came to it, but, on lifting the 

 saucer, I found that I had no need to do more for the larva lay exposed before me — it had 

 formed a cist immediately under the saucer. In this cist it remained inactive until the 

 28th of the month, when it underwent a change. The skin of the three segments next 

 the head divided down the back, and the pupa (6. Fig. 7) made its debut through the opening. 

 The metamorphosis was very striking. Instead of the dark, muddy larva with all its 

 grotesque, tag-like appendages, there lay the bright, clean, yellow pupa, with rudimentary 

 wings and antennae, and with eyes shewing blue through the waxen skin. Spiracles 

 appeared along the sides ; the branchiae had been cast off; the six legs were drawn up 

 under the body. The creature was very sensitive, either to the light or to the slight jar 

 occasioned by the removal of the saucer, or, it may be, to both, for it became uneasy, and, 

 although it could use neither wings nor legs it worked itself out of its cist and made a 

 complete tour of its prison yard, drawing itself along by its formidable jaws, which, at this 

 stage, closely resembled those of the female imago. In a few days a change of colour 

 began to show itself, and gradually the whole body of the insect darkened with the 

 same hue. 



The change to the imago took place in the afternoon of the 12th of July. The skin 

 was rent in the same way as that of the larva had been, and the perfect insect crept from 

 its ruptured envelope. It crawled up a slight framework which I had placed for its con- 

 venience, shook out its wings, and in a few minutes assumed its full proportions. One 

 thing surprised me greatly : I had expected to see a female insect appear from the case, 

 for the mandibles of the pupa had been, as I have said, of the exact size and shape of those 

 of the female imago ; but the creature on making its appearance presented the preposter- 

 ously long and scythe-shaped mandibulae of the male. These frightful appendages are 

 doubtless weapons of offence, for the creature showed its vim by striking with them viciously 

 at my finger. So eau;er was it for a fray, that, in following my hand with repeated snaps, 

 it drove the weapons thiough its own extended wings. 



Although the mandibles of the male 0. cornutus are of use to the insect for attacking 

 a foe, I doubt whether this is the only or the chief purpose for which they are intended. 

 I imagine that in the nuptial flight they are used for grasping the well-defended neck of 

 the female. 



C. cornutus lays its eggs (about 3000 in number) in masses on the stones and piles 

 cting from the river, where they are soon submerged or on the leaves of trees over- 

 hanging the stream. It surrounds and covers them with a white albuminous secretion. 

 The numerous larvae of the insect, which are called "crawlers" by fishermen, furnish a 

 gi-and supply of food to our fresh-water fish, especially to the bass. I purchased lately in 

 Mmtreal a clever imitation of the full grown larva for the angler's use. 



We have now to consider the Case-worm, Ood-worm, Cadow, or Caddis, (larva), 

 Caddis-fly (imago). 



