170 PROFESSOR OWEN ON THE OSTEOLOGY OF 



' diastemata ' in other adult male skulls of Pithecus, at least in the upper jaw. In the 

 skull of the male Morio, no. 2, with the supernumerary molars, the diastema is be- 

 tween 2 and 3 lines wide between the upper canine and the outer incisor on each side. 

 The dental series of the lower jaw is as continuous as in the other male Morio's skull. 



In the adult males of the Pith. Satyrus the intervals between the upper incisors and 

 canines are seldom under 3 lines in extent, and are constant in all the skulls I have 

 examined. 1 have only observed in one skull corresponding interspaces in the lower 

 jaw : the left canine is separated by a space of aline in breadth from the first premolar, 

 and by one of the same breadth from the outer incisor : the right canine is separated 

 from the outer incisor by an interval of between 3 and 4 lines ; but this is evidently 

 due to an abnormal shape and backward twist of the canine on that side. In the 

 upper jaw of the same skull, the right canine has a diastema on each side, that behind 

 being 2^ lines, that in front 1| line in extent ; the left canine is, as usual, in contact 

 with the premolar, but is separated from the outer incisor by an interval of 4^ lines. 



There is the same range of variety in the size of the premolar and molar teeth of the 

 Pith. Satyi-us as of the Pith. Morio : the average fore-and-aft extent of the grinding series 

 is, in the upper jaw 2 inches 2 lines, in the lower jaw 2 inches 6 lines ; the increase, 

 here, being mainly due to the greater size especially in fore-and-aft extent of the last 

 molar. In the great Bornean male Orang's skull, in the Hunterian Museum of the 

 Royal College of Surgeons (Osteol. Catal. no. 5051), figured in the Zoological Transac- 

 tions, vol. ii. pi. 32, the upper molar series is 2 inches 4^ lines in extent : in the male's 

 skull, locality unknown, figured in op. cit. vol. i. pi. 54, the same series has only 1 inch 

 9 lines in extent : in the skull of the adult male Sumatran Orang's skull, the skeleton 

 of wliich is preserved in the Hunterian Museum {torn. cit. plates 49, 50 & 56, figs. 4 & 8, 

 Ost. Catal. no. 5050), the extent of the molar series is just 2 inches. 



Besides the two skulls, nos. 5050 & 5051, of adult male Orangs of the larger species 

 {Pithecus Satyrus) in the Museum of the Royal College of Surgeons, and the skull of the 

 adult male Orang in the possession of the late Mr. Cross of the Surrey Gardens, of 

 which three skulls I published figures and descriptions in 1835 and 1836 ; I have since 

 described the skull of the adult male, no. 5054, Mus. Coll. Chir., of which a figure of a 

 longitudinal section is given in Trans. Zool. Soc. vol. iv. pi. 29 ; and the skull of the 

 adult female, no. 5056, Mus. Coll. Chir.' I have also examined and compared the 

 skulls of the adult Orangs in the Museum of the Garden of Plants at Paris, and in 

 several museums, public and private, in Holland, together with the skulls, thirteen in 

 number, of the adult male great Bornean Orangs, now in the British Museum. 



The results of these comparisons, and of due consideration given to the figures and 

 descriptions by other authors, more especially Temminck, Dumortier, Solomon Mueller, 

 and Blyth, have confirmed me in the opinion expressed in my first Memoir of 1835, in 



' " Descriptive Catalogue of the Osteological Series contained in the Museum of the Royal College of 

 Surgeons of England," 4to. vol. ii. 1853, pp. 761, 762. 



