for entrance, and if the babies are removed, carries them back with 

 great haste, grabbing them by the neck or any part of their bodies. 

 Mice mothers differ in the way they care for the young. At one 

 time an experiment was made with four mothers who had i8 young. 

 We took all the young from their boxes and put them outside. 

 One big, black mother ran around the box and played, paying no 

 attention to the absent little ones; one immediately went to work 

 and fixed up all the nests and the other two dragged the fat, naked 

 babies and put them into the nests without any apparent thought 

 as to where they belonged. Mice cannot be handled in this way 

 until they are about two weeks old. If disturbed before this, the 

 mother may become nervous and in her anxiety she may kill them. 



WHITE RATS (or any variety) are very valuable and less 

 objectionable than mice in some ways, as they have practically no 

 odor and will run around the school-room and "make tricks" which 

 the children enjoy. The children immediately learn the difference 

 in intelligence between the rats and the guinea pigs and rabbits. 

 A box 2'xi'xi' is big enough for the rats' home. It should have a 

 ^-inch wire mesh side and contain a small nesting box 6"x4"x4". 

 This should be an inexpensive little box such as can be obtained at 

 any grocery store. It should be thrown away very frequently. Saw- 

 dust, cork, excelsior, or newspaper may be put on the floor as an 

 absorbent. Both boxes for the mice and rats can be hung by the 

 back on the wall and thus become a part of the school equipment 

 in a very normal way. The class can select a color and the box can 

 be painted, on the outside only, to make it more attractive. If the 

 mice or rats are to be kept where either domestic or wild mice, or 

 rats can disturb them, the wire on the front should be put on in two 

 layers so that an inch or two of space lies between the two surfaces. 

 This is to keep the wild varieties from disturbing the others, as they 

 sometimes bite their toes and tails. Rats should be fed and 

 watered the same as mice. 



GUINEA PIGS — "cavies" — make the most satisfactory pets 

 for the school-room. They are clean, have very little odor, are per- 

 fectly harmless (in fact, too much so, as they do not protect them- 

 selves from the children) and are very friendly. They reproduce 

 rapidly and make very good parents. The only objection to 

 guinea pigs is that they are so short legged that the slightest fall, 

 even from the lap of a child, may paralyze them. However, though 

 this is hard on the animals, the children soon learn to protect them, 



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