THE ANIMAL KINGDOM. 



135 



served for their support; and thus, even if you release 

 the insect, it is injured, for it cannot fly as well as it could 

 before, any more than a bird could if you were to deprive 

 it of part of its wing-feathers. I am quite sure it is only 

 necessary to point out to you that this is really cruelty to 

 animals, although you might not think it; and I hope 

 you will always remember that however insignificant an 

 animal may be, it has its purpose in creation, and that 

 you are not allowed to injure or persecute it. But to 

 continue : we have next the half-winged so called 

 because their wing-covers are half stiff and leathery, 

 whilst the other half is very thin, as in the Water- 

 Scorpion. Then we find insects with only two wings 

 that is, without the wing-cases ; and amongst these are 

 Flies, Gnats, &c. And lastly we have insects without 

 any wings at all, as Fleas, Spring-tails, and Para- 

 sitos, which are minute insects that do not undergo any 

 changes, and live entirely on the bodies of other animals. 



Arachnida,* or Spider-like animals. It was for a long 

 time the custom to call Spiders insects, but they differ in 

 so many ways that they form a separate class. 



Firstly, instead of the bodies being formed of three 

 sections, as in insects, those of arachnidans consist only of 

 two, the head and thorax not being separated, but forming 

 together the part called the Cephalo Thorax. \ 



Secondly, they have always eight legs. 



Thirdly, they do not undergo any changes. 



Fourthly, their eyes vary in number and position, but 

 are never compound. 



Some of the lower forms of arachnidans breathe in the 

 same manner as insects ; but in Spiders and Scorpions, 

 which form the principal members of the group, the 



* Arachnc, a spider (Greek). 



t Cephale, the head ; thorax, the chest. 



