  Uncle George had to go from home for a week, and his two nephews went part of the way to the railway station with him. As they were about to take a short cut through the wood, Uncle George went up to a huge beech tree. He looked very closely at its grey trunk for a time, then stepping back from it about three yards, exclaimed:— “Come here boys! Stand beside me, look closely at this tree, and tell me if you see any strange objects sticking to the bark.” After staring at it for some time, they both declared that they could see nothing upon it. “Go nearer—nearer still! Now, do you see anything?” The boys shook their heads. “Go quite close up to the trunk and examine it,” said Uncle George. “Oh,” said Frank suddenly, “I see queer things like grubs, coloured almost exactly like the bark. Some of them are lighter in colour.” “Look carefully at those lighter ones, and you will find that they are just empty cases.” “So they are,” said Frank, as he touched one with his finger and saw it crush up. “Notice how they are fixed to the bark!” said Uncle George. The boys watched as their uncle placed his pencil under one of the darker coloured objects, and saw that it was slung up to the tree by a loose silken girdle round its middle, while a tuft of fine threads fastened the lower end to the bark. Suddenly, as if it were annoyed at being touched by the pencil, the lower half of the object moved from side to side with rapid jerks. “Why, it is alive,” said Tom. “Yes, of course it is,” said his uncle. “This is another lucky find.” “What are they?” Frank asked. “Can’t you guess, Frank? Don’t you remember my telling you that all the insects were asleep in their cases during winter. “Each of these darker coloured cases contains a white butterfly. They have been here all winter, and they are just about to hatch out.” “How do you know that, Uncle George?” “I know it because the empty cases tell me that some of the butterflies have just hatched out. This is what your cabbage caterpillar becomes after he is tired of feeding. “You have now seen three different stages of the life of this insect. First, the curious eggs laid on the under side of the cabbage leaf; next the greedy caterpillar; and now, the chrysalis or pupa stage. “The caterpillar goes to sleep in autumn as a hard-cased chrysalis, and wakes up in spring a beautiful butterfly.” “How strange,” said Frank. “And will our caterpillars remain caterpillars until autumn, and then tuck “No, Frank! our caterpillars will go into the chrysalis state in a week or so, and hatch out as butterflies in August. These August butterflies will lay eggs. The caterpillars from these eggs will turn into pupÆ in September. “These September pupÆ will supply the white butterflies of next spring and summer. Put some of these into your box. Watch then carefully, and you may be lucky enough to see the white butterfly coming out of his winter case.” “I cannot understand,” said Tom, “how a big white butterfly can be inside so small a case. It must be very tightly wrapped up.” “So it is, as you will see,” said Uncle George. “Good-bye, boys! and mind, when I come back, I shall expect to see notes and sketches of all that has taken place in the larva cage during my absence.” * * * * * * * * “Won’t you let your uncle take his dinner first,” said Frank’s mother, as she hung Uncle George’s overcoat up in the hall. “No, mother! he must come at once,” said the excited Frank. “There’s a butterfly just coming out.” “Oh, I must come and see that,” said Uncle George; and he allowed his eager nephews to drag him towards the larva cage. By the time they got to the cage the butterfly had hatched, but they were in time to see it unfurl its wings. The wings were crumpled and twisted, but the creature slowly straightened them out to dry in the sun. “We saw it burst its case,” said Tom. “First a small slit appeared at the head end. This slit grew larger. Then the butterfly’s head and feet appeared. It squeezed its way and was just half way out, with its wings crumpled round it, when you arrived.” “I arrived just a minute too late, then,” said his uncle. White or Cabbage Butterfly and Pupa. “Oh, and the eggs have hatched too,” said Tom. “Look at them now, Uncle George!” His uncle looked, and saw that the white patches of eggs had given place to larger patches of little active, dark coloured maggots. “We want to know what has become of the lovely carved shells of the eggs,” said Tom. “They have been eaten up,” his uncle replied. “From the moment a caterpillar is born he does nothing “For the first week of their lives these tiny caterpillars feed together in small bands, and they grow so fast you can almost fancy you see them growing. After they have grown to a certain size, each caterpillar starts out for himself.” “Do you see the three butterflies that have hatched out?” asked Tom. “Yes, I see them. There are two females and one male,” said Uncle George. “How can you tell males from females?” asked Frank. “Oh, that is easy enough,” Uncle George replied. “The females are larger, and have two big black spots on each of their front wings. But I only see eight of the large cabbage caterpillars. We put in twelve, I think.” “Look!” said Frank, pointing to the roof of the cage. “Ah, yes, I see them. Two of them have passed into the pupÆ stage, and are slung up by their silken belts to the wall of the cage. “The other two are spinning silken belts round the middle of their bodies, if they have not already done so. After this belt is finished they will slowly slip their useless green skins off, and finally get rid of them by sharply jerking the tail end of their pupa cases.” “Yes, we watched those other two do that,” said Tom. “Notice,” continued Uncle George, “that all your big cabbage caterpillars have lost their yellow stripes “But look at the currant and the hairy caterpillars, uncle,” said Frank. “My dear boy,” said Frank’s mother, “Uncle George must really have food and rest after his long journey. He will hear about the other caterpillars some other time.” Exercises on Lesson XIII.
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