MORE ABOUT MAMMALS. 
21 
the Mammal class, have warm blood. In that 
respect all mammals are alike. 
14. “ Now we must put off the rest of our talk 
about our own class until to-morrow, for there is 
still much to be told.” 
MORE ABOUT MAMMALS. 
1. The next day Mr. Johnson began his talk to the 
boys by saying : 
“ When I tell you that at least three thousand 
kinds of mammals are known, I think you will 
imagine that there are wide differences among them. 
Indeed, I need but name a few — as the elephant, 
bat, whale, mouse, lion, monkey — and we are re- 
minded of such different shapes and habits that you 
may be surprised to find the animals all in the same 
class. Yet they certainly are, for they agree in the 
points I have already described.” 
2. “Are you going to tell us about the different 
kinds?” asked William. 
“Yes; I will show you how we arrange the large 
class of three thousand into groups, which we call 
orders. In doing this the feet and the teeth are 
our chief guides. 
3 . “ First amongst the orders of Mammals we will 
place Man, the two-handed creature, and the only 
one which walks erect. 
