Water Insects.—Aquaria.

One July afternoon the boys had been fishing, and to seek some shade and coolness while eating their lunch, they had driven the yacht into a quiet pool among the reeds, which almost met over them. The water below them was very clear and still, and as it was only about two feet deep they could see the bottom quite plainly, and they soon found that it was well worth a close inspection. The pool was teeming with insect life. The surface of the water was covered with tiny whirligig beetles, which were skimming about in mazy, coruscating evolutions.

"Those whirligig beetles," said Dick, "have their eyes made with two faces—one to look down into the water, and the other to look into the sky."

"What a lot you have learnt about insects, Dick, in the course of a few months," said Frank.

"It is a grand study," said Dick enthusiastically; "and I have worked my best at it. When one goes hard at a thing it is astonishing how soon one picks up a lot of knowledge about it. I have read over and over again about the common insects, or those that are the most noticeable."

"Well, tell us about all those insects we see now."

"Look at those long-legged narrow-bodied flies which are sliding along over the surface. These are called water-measurers. That oval beetle which is swimming on its back, and using two legs like oars, is the water boatman. It fastens on to the head of small fish, and soon kills them. It lives in the water, but if put on land it can fly. Look at that brute crawling over the mud, with its lobster-like head. It has sharp claws and a hollow snout. It lies in wait for its victims, and when it seizes them it sucks the juice out of them with its beak. It looks only of a dull brown now, but when its wings are expanded its body is of a blood red colour, and its tail is forked. It sometimes comes out for a fly at night."

"And what is the fearfully ugly thing climbing up that reed-stem just out of the water?"

"Oh, that is the larva of the dragon-fly. The fly is about to come out of the case. Just watch it for a while."

The larva of the dragon-fly is one of the ugliest of creatures. It has a long light-brown body and six legs. It has a fierce wide mouth and projecting eyes. Attached to its head are two claws, which with a pincer-like movement, catch up anything eatable and pass it to the mouth. In its larva and pupa state it has just the same appearance, and when it is about to change into a perfect dragon-fly it climbs up out of the water and emerges out of its case, just like the butterfly, and sails away a perfect and gorgeous insect, leaving its case a transparent brown shell, still clinging to the reed or grass-stem on which it contracted its last change.

"Bother the gnats!" said Jimmy brushing some off his face. "There is nothing interesting about them."

"Oh yes, there is," said Dick. "They lay their eggs on the surface of the water, making a raft of them, and the larvÆ escape through the bottom of each egg into the water; and I have read that it is a very pretty sight to watch the perfect insect coming out."

"I would prefer their staying down below; they bite me," answered Jimmy.

Crawling along the bottom were numbers of caddis-worms in tube-like cases made of sticks and stones. Inside these cases are the plump white grubs which turn into flies.

"Where the bottom is gravelly these caddis-worms make their cases of little stones," said Frank.

"Yes, and I read the other day that an experiment had been tried by some one, who took some out of their nests and put them into an aquarium with some finely-broken glass of different colours, and the caddis-worms made their cases of this broken coloured glass, and very pretty they looked."

"Their own bodies must supply the glue which fastens the pieces of gravel or glass together?"

"Yes, it does."

As the fish were biting very badly the boys left the broad early and went for a stroll. While passing through the village they saw a sale of stock going on in the open space round which the houses were ranged. They stopped to look on. The goods which were being sold were the stock in trade of a chemist, and among them were three large glass bowls, such as are used for aquaria. These were put up by the auctioneer in one lot, but there was no bid for them. They were articles not in request in that rural district.

"Will no one make me a bid? Everything is to be sold without reservation," cried the auctioneer.

"Five shillings," said Frank.

"Going at five shillings!—going! going!—gone!"—and the lot was knocked down to Frank.

"What are you going to do with them?" asked Jimmy.

"Make them into aquaria, of course. Don't you see they are just the thing. The idea came into my head as soon as I saw them."

"Then we can put some water insects in," said Dick.

The glass reservoirs were placed on a shelf in the boat-house, and the next morning before breakfast they were fitted up. They got a quantity of fine gravel and sand, and thoroughly washed it in water, so as to cleanse it from all mud and impurity. This was placed to the depth of a couple of inches in each vessel, and a rock-work of worn flints was built upon it. Water was poured in to within a few inches of the top, and pieces of anacharis were planted in the gravel, their roots kept down by the stones. In a day or two the water had got clear, and the plants had taken root, and the boys proceeded to stock the aquaria. The small brook near afforded minnows and sticklebacks in plenty. In a stagnant pool they got some newts and water-insects. From the broad they obtained a few small perch, roach, and bream, and an eel about six inches long. They at first put these all together without any attempt at sorting them, and then the following consequences ensued. The water-boatmen fastened on the heads of the small fish and speedily killed them, and ate them up. The sticklebacks made themselves at home at once, and proved very pugnacious, fighting each other, dashing at a stick or finger, if put into the water, but, worst of all, annoying the minnows. Each male stickleback took up a position of his own, and resented any approach to within a few inches of it. With his glaring green eyes, and scarlet breast, he would wage war against any intruder; and when an unsuspecting minnow came within his ken he would sidle up to it, till within striking distance, then dash at it, and strike it with his snout in the stomach. The perch swallowed the minnows, and when they had vanished, attempted to swallow the sticklebacks, but the spines of the latter stuck in the perches' gullets and choked them. The eel, too, would writhe and poke through the gravel and stir it up, displacing the weeds and doing a lot of mischief.

This led to a general reconstruction of the aquaria. The perch were taken out and restored to the broad, together with the eel. The roach, bream, and minnows, were put into two of the aquaria by themselves, and the sticklebacks and water-insects into the other. Many a fight took place among the sticklebacks and the water-boatmen, in which sometimes the one and sometimes the other came off victorious.

Smooth Newt.