DADDY-LONG-LEGS, CENTIPEDES, AND MILLIPEDES. 139 



pairs of legs, and in no species are there less than ten pairs of 

 legs. The true insects alone have wings. 



119. In the growth or development of the true insects 

 and spiders, the young animal comes from the egg with its 

 full number of segments complete, while in the myriopods 

 the young animal comes from the egg with a few segments, 

 and new ones are added as the animal grows. 



Some of the characters of the insects, spiders, and myri- 

 opods, may be represented as f olTows : 



V 



1 2 8 



Three pairs of legs, and having wings. 



Tktte Insect. — Body divided into Three Eeglona. 



12 3 4 



Four pairs of legs. 



Bpidee. — Body divided into Two Kegions, Head not separate. 



WM^ 



No definite number of legs 



Mthtopod. — Body not divided into Eeglons, but Head separate. 



'Fia. 120.— Animals whose Bodies aee composed of Segments possessing Jointed Legs, 



AND EREATSING AlR THEOUQH OPENINGS IN THE SiDES OF THE BODT. 



On account of some of these characteristics above men- 

 tioned, with others not mentioned, being held in common by 

 the true insects, spiders, and myriopods, these creatui'es form 

 a natural group in the animal kingdom, just as the snails, 



