80 NATURE STUDY. 



and markings ; two houses may be very similar in plan, 

 and yet differ greatly in size, color, and markings, or 

 trimmings or decorations. Hence it is wise to begin 

 the comparison with two quite similar animals, to dwell 

 on essential similarities rather than differences, and to 

 emphasize these similarities, bring them into stronger 

 relief, by contrasting these similar animals with those 

 quite dissimilar. 1 



Comparison and classification require very careful 

 questioning or development work by the teacher. Dis- 

 tinguishing between essentials and non-essentials re- 

 quires knowledge and judgment ; abstracting and 

 applying plan demands some intellectual power. Hence 

 in this work the pupils need considerable guidance and 

 help. 



1 The most essential features in the classification of the rabbit 



are : 



The bony skeleton and backbone or vertebral column, placing it among: 

 the vertebrates. . 



The hairy covering or fur, placing it among the class of vertebrates 

 called mammals. 



The way in which it feeds and the character of the teeth, two large 

 incisors, and the molars in each jaw, with no canine teeth, show- 

 ing that it belongs with the order of mammals called "gnawers" 

 or rodents. 



The long ears, short tail, and two small accessory incisor teeth, hidden 

 behind the large incisors of the upper jaw; these are characteristic of 

 the family of hares (the leporidae), including the rabbits. 



The ears, shorter than the head, and the habit of burrowing in the ground, 

 distinguish the rabbit from the hare. 



These essential features are given here merely to assist the teacher 

 and give point to the lessons which follow. They should be gained from 

 the children, as a result of their observations and comparison, never 

 merely given to the pupils. 



