DADDY-LONG-LEGS, CENTIPEDES, AND MILLIPEDES. 129 



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 conies from the egg with its 

 full number of segments complete, while in the myriapods 

 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- 

 apods, may be represented as follows : 



i 



Three pairs of legs, and having wings. 

 TRUE INSECT. Body divided into Three Eegions. 



12 34 



Four pairs of legs. 

 8pn>EB.--Body divided into Two Regions, Head not separate. 



nvm 



No definite number of legs 



MTRIOPOD. Body not divided into Eegions, but Head separate. 

 FIG. 120. ANIMALS WHOSE BODIES ARE COMPOSED OP SEGMENTS POSSESSING JOINTED LEGS, 



AND BREATHING AlR THROUGH OPENINGS IN THE SlDES OF THE BODY. 



On account of some of these characteristics above men- 

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

 the true insects, spiders, and myriapods, these creatures form 

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



