CANADA PORCUPINE 9 



life? Will the porcupine conform to or depart from the law of 

 direct ratio of length of infancy and degree of plasticity? 



The limitations which circumstances have thrown around 

 direct knowledge of the infant porcupine and consequently upon 

 exact judgments concerning it are fully appreciated. One can 

 do little more than state the problem at this time. Even to 

 anticipate a whole series of results by saying that the porcu- 

 pine has not shown indications of the arrest which characterizes 

 animals of short infancy, but has proved very adaptable under 

 widely varied circumstances and through a great range of ages, 

 there is presented possibly only a wide variation from a very 

 general rule. This later plasticity is evident. The short period 

 of infancy is strongly suspected, but we must wait at least until 

 the living infant has been seen by some one, until it has been 

 observed critically and subjected to tests as other animals have 

 been, until its nervous system at birth has been examined, before 

 concluding positively on the conformity or non -conformity of 

 the porcupine to the general rule of the significance of infancy. 

 It need only be added that if the period of gestation is seven 

 ■ months, as Brehm claims and as is the case with the Old World 

 species, some of the infantile stages may be included in the long 

 prenatal state. 



Play. — No one has ever seen a porcupine play. In fact, play 

 seems so foreign to the porcupine's nature that it would be a 

 matter for surprise to see one of them turn a trick in pure amuse- 

 ment. They frequently quarrel, rarely slap each other, more 

 rarely still seize each other by the quills, but an encounter is 

 seldom seen in which it does not appear that each participant 

 would rather the contest had not occurred. This, however, is 

 an anthropomorphic view-point given for the purpose of making 

 clear the habits of the porcupine. It is not considered safe to 

 infer that any animal is playing when it makes many quick 

 movements, nor that slow movements indicate a serious type of 

 mentality. It is imperative for the porcupine's survival that 

 they move slowly except when hard pressed by an enemy. The 

 maximum of pleasure might well go along with slow movements 

 and a minimum of danger. On the other hand, the quick, rest- 

 less spontaneity of a young animal or even a child may well 

 represent a more serious mental disposition than adult human 

 beings ordinarily suspect. The term play is used in its broad 

 sense. In this popular sense, porcupines do not play. 



