THE CRANIAL SUTURE CLOSURE IN MONKEYS*

Abstract

Summary. A study of the age changes in the skull, as represented by the ecto‐and endocranial suture closure, has been made. The material investigated consists of 1500 monkey crania belonging to ten different genera of the Old and New world. The methods of study are described and the existing literature on the suture closure is reviewed. From an investigation of a large series of monkeys it has been possible to report in detail the relative ages and the sequence of cranial suture closure typical for each genus studied. It is recorded that the sutures close at a comparatively earlier age in apes than in monkeys or in man. Generally speaking the sutures close at a later stage in most platyrrhines than in catarrhines. The variability of cranial suture closure is discussed. study of the behaviour of the sutures in monkeys no major species or sex differences could be found. The occurence of Inca bones, divided parietals and cases of metopism, encountered in monkeys during the course of the present investigation, have been described with special attention to its comparative frequency.