540 PROCEEDINGS OF THE NATIONAL MUSEUM. vol. xxxi. 



by Diimortior, Dolisle, Owen, Seletika, A\'!iIkhotf, etc.. for anthropo- 

 logical comparisons, and also form a basis for the collation of orang 

 skulls from other localities. 



The (}Ucstion as to which species of orangs the crania belong must for 

 the present remain unanswered, on account of the existing uncertain- 

 ties as to the species-distinguishing marks on the skull. Presumably, . 

 the animals are nearest related to the "Landak race" of Selenka. 



The technical terms in the description are those that are in general 

 use in craniometry and anatom3\'^' 



OBSERVATIONS. 



A(/e. — The tirst problem in the examination of Doctor A))bott's 

 series was how to determine the fulh^ adult skulls from those of 

 younger animals. It was found that: 



(1) No reliance can be placed on the condition of the sutures of the 

 cranial vault as indicative of age. The lambdoid and then the sagit- 

 tal, both of whicii in man remain open long into adult life, in the 

 orangs begin to svnostose even before the completion of the second 

 dentition; and the coronal, in its superior half, soon follows in occlu- 

 sion upon the sagittal suture. The inferior portion of the coronal and 

 the temporo-parietal articulation are more stable and become fully 

 oblitei-ated only about the time when other signs indicate that the 

 growth of the animal has been completed. Thus it is onl}^ the state 

 of these last two sutures that may aid in determining the adult period. 



(2) The facial sutures remain patent longer than most of those of 

 the cranial vault. The first to synostose is the intermaxillary artigida- 

 tion, the next those of the malar Ijone, and last of all the nasal, and 

 pieces of one or two orbital sutures. The closure of the intermaxil- 

 lar}" articulation precedes the attainment of full growth; that of the 

 malar sutures is about cotemporary; while parts of the nasal articida- 

 tions and an orbital segment or two may persist open for some time 

 after the adult stage of life has l)een attained. 



(3) Obliteration of the basilar suture seems to correspond very 

 closely with the reaching of full growth, and, as in man, it will be 

 found of all the signs the most reliable in separating adult from 

 younger orang crania. 



( t) The completion of the second dentition in oi'angs is not a criterion . 

 that the adult life has ))een reached, for it takes place before the full 

 growth of the animal is achieved. The wear and pitting of the teeth 

 begin also during adolescence, soon after the eruption of the third 

 molars. 



(5) In males the fusion of the temporal ridges and the formation 

 therefrom of a sagittal crest appear to correspond closely with reach- • 



"See Quain's or Cunningham's Anatomy, or Topinard's Anthropology. 



