PUZZLES AND PARADOXES 265 



Mice and rabbits, and even bears, if they are much, dis- 

 turbed, will eat their young when newly born. 



Parental solicitude, however, is the rule. Even among 

 the lowliest creatures we seem to find convincing 

 proofs of this. We say " seem " advisedly. For while 

 there can be no doubt about the reality of the anxiety 

 displayed by beasts and birds for the welfare of their 

 young, it is not so easy to estimate the degree of conscious- 

 ness which creatures like bees, wasps, ants, spiders and 

 scorpions, beetles, sea-urchins and sea-slugs appear to 

 exhibit. The two last, at any rate, can surely hardly be 

 credited with the conscious care of their offspring; yet 

 at least one species of sea-urchin carries its eggs in a pouch 

 on its back, while the sea-slug carries its young on its 

 back. Many spiders, and the book-scorpion, carry their 

 eggs in a silken bag, attached to the under surface of the 

 body. Of the true scorpions some carry their young 

 on their backs, while on the subject of the bee and the 

 ants whole volumes might be, and indeed have been, 

 written on their domestic economy. 



Though all sorts and conditions of Infants have now 

 been surveyed in these pages, one inference certainly 

 seems to be justified, and this is that the course of develop- 

 ment from the egg to the adult is one of more or less 

 continuous betterment. But this, apart from the facts 

 furnished by a study of parasites, is by no means universally 

 true, for we meet with cases of physical degeneracy of a 

 most extraordinary kind. The most striking of all, without 

 doubt, is that furnished by the young of certain curious 

 animals which, in their adult stage, may be described as 

 animated jelly-bags. Many of my readers will recognise 

 them. under the name of sea-squirts, for they are common 

 enough on rocks and seaweed, at low tide, at most places 



