2 APES AND MONKEYS 



In order to appreciate more fully the value of the lessons 



to be drawn from the contents of this volume we must 

 know the relative planes that men and monkeys occupy in 

 the scale of nature. Within the limits of this work, how- 

 ever, Ave can only compare them in a general way. Since 

 monkeys differ so widely among themselves, it is evident 

 that all of them cannot in the same degree resemble man ; 

 and as the degree of interest in them is approximately 

 measured by their likeness or unlikeness to man, it is 

 apparent that all cannot be of equal interest as subjects of 

 comparative stud}'. But since each forms an integral part 

 of one great scale, each one is equally important in tracing 

 out the continuity of the order to which all belong. 



The vast family of simians has perhaps the widest range 

 of types of any single family of animals. Beginning with 

 the great apes, which in size, form, and structure so 

 closely resemble man, we descend the scale until it ends 

 in the lemurs, which are almost on the level of rodents. 

 The descent is so gradual that it is difficult to draw a line 

 of demarcation at any point between the two extremes. 

 There is now, however, an effort being made to separate 

 this family into smaller and more distinct groups ; but the 

 lines between them are not sharply drawn, and the litera- 

 ture of the past has a tendency to retard the effort. But 

 we shall not here assume to discuss the problems with 

 which zoology may in the future have to contend ; we 

 shall accept the current system of classification and pro- 

 ceed along that line. 



In the language of the masses all the varied types that 

 belong to the simian family are known as monkeys. This 



