ADOLESCENCE 213 



and great " slackness " ; but the general statement seems to 

 us to be safe, that a rapidly growing adolescent is naturally 

 a good deal preoccupied we mean, of course, organically, 

 not consciously, preoccupied with his or her internal 

 affairs. This means that he or she should have plenty of 

 rest and plenty of play. 



Our second note concerns internal rearrangements. If 

 we take a wide survey of adolescent animals, and mark 

 the beginning of the adolescent period by the assumption 

 of definitely adult characters and the laying aside of dis- 

 tinctively juvenile characters, then we must include in our 

 conception of adolescence the idea of internal change, 

 rearrangement, and readjustment. There is often among 

 animals a well-marked juvenile period, as we have seen, as 

 of caterpillars or of tadpoles, of kittens or of chicks ; there 

 is often a well-marked adult or mature period, of butterflies 

 or of frogs, of cats or of hens ; between the two lies the 

 ill-defined adolescent period, the biological hobble-de-hoy 

 phase, when the creature is neither juvenile nor adult, 

 but between the two. In this period there are often re- 

 adjustments and new adaptations. There may be increase 

 of complexity (differentiation) or the establishment of 

 more perfect unity (integration) the two criteria of all 

 organic progress, whether individual or racial. The ado- 

 lescent creature is more complex than it was from its teeth 

 to its nerve-paths ; it shows the structural results of 

 increased division of labour ; it differs from its juvenile 

 phase as the locomotive of 1910 differs from Stephenson's 

 " Puffing Billy/' But it also becomes more controlled, 

 unified, harmonious, more vertebrated and knit together ; 

 its character becomes set ; it gets a purpose in life. From 

 its plastic juvenile stage often so delightfully irresponsible 

 it differs in integration, just as the locomotive of 1910 

 differs from " Puffing Billy." 



