422 NATURE STUDY AND LIFE 



comparison. Has every one a worm ? They should all 

 have an earthworm or a leech. What is the main differ- 

 ence between the worm and all the rest .'' While it is 

 made up of segments, somewhat like many caterpillars 

 and grubs, it has no legs. What difference can the 

 children discover between the mouth of a worm and that 

 of a grub or caterpillar .■■ The children have had occasion 

 to observe various caterpillars as they eat the leaves by 

 gnawing off particles with their sharp jaws. What does 

 an earthworm eat, and how does it manage without either 

 jaws or teeth .' What child will volunteer to find out and 

 tell the class .' What does a leech eat .' Boys who have 

 been in swimming or who have caught fishes with leeches 

 attached to their gills can tell. Hereafter we shall try 

 to distinguish between worms and the larvae of insects, 

 and we can tell most of them, apart at a glance. Several 

 marine worms are provided with sharp hooks or teeth, 

 but they have no legs. 



Next, what chief differences do they see between a 

 spider and an insect .' The insect is divided into three 

 parts, viz., a head, chest, or thorax, and abdomen ; the 

 spider into two, — head and chest united and abdomen. 

 Further, all insects have six legs, no more nor less, and 

 most of them have one or two pairs of wings. Do any 

 spiders have wings .' How many legs do spiders have ">. 

 Eight. Hereafter, then, we will try to call spiders, 

 spiders, and not insects. We have found, too, that 

 insects go through wonderful transformations, the egg 

 hatching into a larva, the larva changing into a pupa, 

 the pupa finally transforming into the perfect insect like 

 that which laid the egg. What hatches from a spider's 



