28 The Under-Water World 



perches of tropical countries make deep 

 pits in the sandy streams which are 

 guarded by the parents in turn. The 

 fathers of the Chinese paradise fish and 

 allied forms construct fairy-like bubble 

 nests, in which the eggs are deposited 

 one by one. The nests are formed of a 

 sticky secretion and are blown on the 

 surface of the water. The female of the 

 so-called Nile Mouth-breeder incubates 

 the eggs about sixty in number in her 

 mouth, and many other fishes will gather 

 the brood into their cheeks should danger 

 threaten. The male topsail a marine 

 cat-fish inhabiting the South Atlantic, 

 has a cavernous mouth in which about 

 100 large eggs are incubated. They are 

 retained in the mouth until the yolk sacs 

 are completely absorbed and the young 

 are able to fend for themselves, a period 

 which may extend over two and a half 

 months. Whilst thus protecting his pro- 

 geny the father takes no nourishment 



