252 SEA-SIDE STUDIES. 



from it. The reptile, equally incapable of appreciating 

 the pleasures connected with maternal care, is content 

 to leave her eggs exposed to the genial warmth of the 

 sun until the included young escape. But no sooner 

 does the vital heat of the parent become sufficient for 

 the purpose designed by Nature, than all the sympa- 

 thies of parental fondness become developed." * This 

 is a very plausible generalisation ; but there are facts 

 which peremptorily contradict it. On the one hand, 

 there are cold-blooded vertebrates — fishes, such as the 

 Hassar, Goramy, Stickleback, Lepidogaster, and Syn- 

 gnathus — which make nests, or sit on their eggs. On 

 the other hand, there are warm-blooded vertebrates — 

 birds, such as the cuckoo and American cowbird, 

 which, utterly regardless of maternal delights, leave 

 their eggs to be hatched by other birds. 



The fishes contradict our generalisations on many 

 other topics ; and a very curious passage in Natural 

 History might be written by any one who should take 

 the trouble to collect and group together what may be 

 called fish-paradoxes. Thus there are fish that fly ; 

 fish that climb {Percha scandens) ; fish that hop, like 

 frogs, using their fins as veritable legs {Lophius) ; 

 fish that ruminate (the carp) ; fish that discharge 

 electricity in sufficient intensity to decompose water ; 

 fish that migrate ; fish that make nests ; fish that in- 

 cubate ; and fish that bring forth their young alive. 



Fish that sing have not yet been heard, but that 

 some of them make an approach to vocal performances 



* Rymer Jones, General Outline of the Animal Kingdom, p. 615. 



