“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 and are now of a bluish green colour. They have stopped feeding, and are now dull and sleepy. This indicates that they are about to enter the pupa stage.”
“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.
1. Explain why the pupæ of white butterflies are coloured like the objects they are attached to. 2. Write the life of a white butterfly, and illustrate your description with sketches of caterpillar, pupa, and butterfly. 3. The life of an insect is divided into four distinct stages. Name them. Which is the longest stage in the case of the white butterfly? 4. Describe, as you have observed it, the behaviour of a caterpillar as it passes from the larva to the chrysalis form.
XIV.—THE TOILING CADDIS.
“Look here, boys,” said Uncle George, “you have been paying nearly all your attention to the larva cage during my absence, and have forgotten the caddis worms.”
