  During summer the boys paid many visits to the horse pond. Each time they went there they saw something to interest them. Their uncle taught them to keep perfectly still while looking into the water. They soon came to know that this was the best way to study pond-life, for, whenever they moved, the creatures they were watching would dart out of sight. One day, while they were both lying on the bank gazing into the pond, a huge black beetle came up to the surface of the water. It remained there for a few moments, with its head hanging downwards and its tail sticking right out of the water. Then it dived down out of sight. In a few minutes it came up again, and this time Frank’s net was under it before it could escape. Just as Frank was putting it into the glass jar, Tom whispered, “Here is another one—quick, Frank!” But Frank was too late; for before he could get the first beetle into the jar, the second one had dived to the bottom of the pond. The boys waited for a long time, hoping to see the other beetle again. At last their patience was rewarded. The beetle came up again to the surface. As soon as it did so, in went the net, and out came beetle number two. “What big beauties,” said Frank. “I wonder what they are. Let us hurry home and show them to Uncle George.” When they got home, their uncle placed the two beetles in a glass tank by themselves, so that they could be more easily observed. “What do you call them, uncle?” asked Frank. “We have never seen such large, handsome beetles before.” Dyticus Beetle, male and female. “Have you not?” his uncle replied. “I am surprised at that, for this beetle is found in nearly all our ponds and ditches. It has a long Latin name, And Uncle George handed Frank a small measuring rule which he carried in his pocket. Frank looked at the beetles, and then moved his thumb nail along the rule. “About an inch and a half in length,” he said. “That is about right,” said his uncle. “Are these two beetles exactly alike?” “They are both about the same shape and colour. One is slightly bigger than the other. They are both greenish-black above and brown below. There is a curious broad border of yellow all round the edge of their bodies,” said Tom. “But they are not both exactly alike,” said Frank, “I notice that one is smooth on the back, while the other’s back is all grooved.” “You are right, Frank,” said Uncle George. “The one with the grooved wing-cases is the female. The one with the smooth cases is the male. Fore Leg of Male, showing Sucker Organ. “Notice the long legs they have for swimming, and how they seem to oar themselves through the water. Notice also that the male has a large flat disc upon each of his fore legs. These are suckers, by which he can cling to things.” “Why do they come up to the surface so often?” Frank asked. “They cannot live without air. They carry a supply of air under their wing-cases. They just come up to renew it from time to time. This is done by thrusting the end of their bodies out of the water as you see.” “One would think they ought to thrust their heads out to get air,” said Tom. “That seems more natural to us, because we breathe with our mouths,” said Uncle George. “These animals take in air with their tails. A great many pond insects breathe in this curious way.” “What do they feed upon?” Frank asked. “They are fierce, greedy creatures,” his uncle replied. “They attack and kill worms, tadpoles, and even small fishes.” Uncle George threw a small worm into the tank. One of the beetles seized it at once and began to devour it greedily. Presently the other beetle seized an end of the worm. The boys watched closely, and saw that the beetles’ jaws moved from side to side like a pair of pincers. Next morning, when Uncle George and the boys went in to see the beetles, they found only one in the tank. The other had escaped during the night. After a careful search they found it, at the far end of the room, dead. “Now, how do you think this beetle managed to get out of the tank and travel all that way?” Uncle George asked. “It must have crawled up the inside of the tank, then down the outside. Then it must have fallen off the window-sill, and crawled right across the floor,” said Frank. Uncle George shook his head. “It might,” he said, “have managed to crawl up to the edge of the tank so long as its legs were wet. But as its long legs are made for swimming, and not for crawling with, I can hardly see how it could have crawled or walked all that distance.” “Then how did it get there, Uncle George?” In answer to Frank’s question, his uncle took the dead beetle, and placed it on a piece of paper on the table. He next moved aside each of the large black wing-cases with a pin. Underneath these wing-cases the boys saw a pair of large wings neatly folded up. Uncle George removed one of the wing-cases, and unfolded one of the wings. “Why, these beetles can fly,” said Tom. Male and Female Beetles, showing Flying Wings. “Of course they can,” said his uncle. “All beetles can fly. This creature has evidently been flying about the room all night. These insects are furnished with wings, so that they may be able to fly to another pool when food gets scarce, or when their pool dries up.” Exercises on Lesson VI.
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