[ 165 ] 
XIII. Osteological Contributions to the Natural History of the Orang Utans (Simia, 
Erxleben). By Ricuarp Owen, Esq., F.R.S., &c., Hunterian Professor of Ana- 
tomy at the Royal College of Surgeons. 
Communicated October 25, 1836. 
THE interest which is attached to the Orang Utans, their rarity and limited geogra- 
phical distribution, and the obscurity which still envelopes the history of the species 
which appertain to the genus Simia as limited by Erxleben, induce me to offer to the 
Zoological Society some additional observations on that subject, which I hope may 
contribute to extend and establish our knowledge of those remarkable anthropoid in- 
habitants of the forests of the larger islands of the Indian Archipelago. 
These observations relate only to the skull and teeth,—parts of the osseous system, 
however, which each day’s experience seems to indicate as the principal points from 
which the best and surest specific as well as generic differences may be derived. The 
descriptions are accompanied with drawings of the objects described of the natural size. 
The first part of this paper describes an interesting stage in the change of the teeth in 
the great Orang of Borneo (Simia Wurmbii) ; the second part relates to a skull of an 
Orang in which that change had been completed, but which retains proportions and 
presents a form apparently specifically distinct from those in any other known 
species. 
Hitherto the proof of the immature state of the so-called Simia Satyrus has been de- 
rived from the discovery of the germs of large permanent teeth, hidden within the cavity 
of the jaw-bones'. In the specimen now before the Society, (P]. XXX., figg. 1, 2, 3.) 
some of the permanent teeth have come into use, and have displaced their puny prede- 
cessors. 
' Since this paper was read, the Livraison of the Monoyraphies de Mammalogie of M. Temminck, containing 
the important observations of its distinguished author on the rich collection of osteological and stuffed specimens 
of the Simia Satyrus in the celebrated Museum at Leyden, has been published. The wrapper of the Livraison 
bears date 1835, but reference is made in the text, (p. 122) to a letter received by M. Temminck, from 
Borneo, bearing date the 5th of October, 1836. It would have been unpardonable in me to have neglected the 
writings of so great an authority on the subject of the Orangs, had they been accessible at the time when the 
abstract of the present memoir was published in the Proceedings of the Zoological Society. 
The following is a summary of the observations recorded by M. Temminck on the progress of dentition in 
the Orang of Borneo. 
In an individual, 1 foot 5 inches high, all the deciduous teeth are in place; they correspond in number and 
kind with those of the human subject; but the molars of the lower jaw are larger; none of the permanent teeth 
are developed. 
VOL. I1.—PART III. Zz 
