The Study of Animal Life 



themselves, his cares are increased tenfold. It is hard to 

 keep the youngsters in the cradle. " No sooner has he 

 brought one bold truant back, than two others are out, and 

 so it goes on the whole day long." 



We are not clever enough to understand why the males 

 among many fishes are so much more careful than the 

 females. For the stickleback is not alone in his excellent 

 behaviour. The male Chinese macropod (Poly acanthus) 

 makes a frothy nest of air and mucus, in which he places 

 his mate's eggs. He, too, watches jealously over the brood, 

 and "has his hands — or rather his mouth — full to recover 

 the hasty throng when they stray, and to pack them again 

 into their cradle." Of all strange habits, perhaps that 

 is strangest which some male fish (e.g. Arius) have of 

 hatching the eggs in their mouths ; what external dangers 

 must have threatened them before this quaint brooding- 

 chamber was chosen ! Or is it not almost like a joke to see 

 the male sea-horse swelling up as 

 the eggs which he has stowed 

 away in an external pocket hatch 

 and mature, "till one day we 

 see emerging from the aperture a 

 number of small, almost transpar- 

 ent creatures, something like 

 marks of interrogation." But 

 some female fishes also carry 

 their eggs about, attached to the 

 ventral surface (in the Siluroid 

 fish, Aspredo), or stowed away in 

 a ventral pouch (in Solenostoma, 

 allied to pipe-fishes), arrange- 

 ments which recur among amphi- 

 F,G ^4»7»S). ( fl^m Wans, but on the dorsal surface 



Evolution of Sex ; after Atlas of the body. 



of Naples Station.) . .... . 



Amphibians, like fishes, to 

 which they are linked by many ties, are either quaint or 

 careless parents. Again, the males assume the responsi- 

 bilities of nurture. The obstetric frog (Alytes obstetricans), 

 common in some parts of the Continent, takes the eggs from 



