REPTILES — BIRDS 



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Classification op Reptiles 



Oeder 1. Chelo'nia (turtles and tortoises). Flattened reptiles with body inclosed in bony 

 case. No teeth or sternum (breastbone). Examples: snapping turtle, box tortoise. 



Order 2. Lacertil'ia (lizards). Body covered with scales, usrally having two-paired appen- 

 dages. Examples : fence lizard, horned toad. 



Orders. Ophid'ia (snakes). Body elongated, covered with scales. No limbs present. 

 Examples: garter snake, rattlesnake. 



Order 4. Crocodil'ia. Fresh-water reptiles with elongated body and bony scales on skin . 

 Two-paired limbs. Examples: alligator, crocodile. 



Birds. — Birds are distinguished from all other animals by their covering 

 of feathers, which are developed from the skin. These aid in flight and protect 

 the body from the cold. 



Bills and feet of various birds : 1, ostrich ; 2, sparrow ; 3, hen ; 4, eagle ; 5, heron 

 6, gull ; 7, pigeon ; 8, woodpecker ; 9, parrot ; 10, kingfisher. 



The form of the bill shows adaptations to a wonderful degree. A duck has 

 a flat bill for pushing through mud and straining out food ; a bird of prey has a 

 curved or hooked beak for tearing ; the woodpecker has a sharp, straight bill 

 for piercing the bark of trees mEHEAo 



in search of insect larvae 

 which are hidden underneath. 

 Birds do not have teeth. 



The rate of respiration and 

 of heartbeat and the body 

 temperature are higher in the 

 bird than in man. Man, 

 according to age and other 

 conditions, breathes from fif- 

 teen to twenty times a min- 

 ute. Birds breathe from 

 twenty to sixty times a min- 

 ute. Because of the increased 

 activity of a bird, there comes a necessity for a greater supply of oxygen, an 

 increased blood supply to carry the material to be used in the release of 

 energy, and a means of rapid excretion of the wastes resulting from the 

 process of oxidation. Birds are large eaters, and the digestive tract is fitted 

 to digest the food quickly. As soon as the food is part of the blood, it may be 

 sent rapidly to the places where it is needed, by means of the strong four- 

 chambered heart and large blood vessels. 



Diagram of a bird, showing names of various 

 parts. 



