24 



Lessons in Zoologi/. 



Fig. 7 



yellow crust from the edges of mine, and there's a little 

 dark brown wire left. I can see lots of little dots all over 

 mine. They look like pin-holes. 



All are now interested to 

 learn that the " yellow crust " 

 is the flesh that connected all 

 the animals of the colony, and 

 the " brown wire " is the skel- 

 eton. The flesh contains so 

 many bits of lime that it be- 

 comes hard when it dries, and 

 so remains on the stems. The 

 skeleton is horny. In order 

 to understand what the " pin- 

 holes " are we must turn to 

 the diagram of the red coral (Fig. 7), which the children 

 describe : 



There is red flesh between the coral animals. The 

 coral animals are white. They have only eight tentacles. 

 The tentacles are fringed. One of the coral animals has 

 drawn itself back into the red flesh, and only its tentacles 

 show. Two other coral animals have drawn themselves 

 all back into the red flesh, and there's only a little bit of 

 white in a round, red place to show where they were. 



It is now easy to see that the animals which make the 

 Galaxea and the finger-coral could not hide so nicely in 

 the flesh that covers the branch because the stony tubes 

 would be in the way, and to draw the conclusion that the 

 red coral has no separate tubes. Neither does the fan- 

 coral animal make tubes. 



Skillful questions now lead the pupils to see that if the 

 red-coral animals die, and the flesb dries, a red stem 

 will be left with dried flesh on it, and in the flesh little 

 holes that show where the animals were. So they know 



