6 
PRIMROSE : THE ANATOMY OF THE ORANG OUTANG 
fashion. Thus, Fick^ states that the lower lip may be protruded so as 
to form a kind of natural cup, so that if, for example, milk be given to 
the creature, he can fill this cup formed by the protruded lip, and then 
proceed to sip or lap the milk out of it. Darwin^ refers to the protru- 
sion of the lips in discussing the expression of the emotions in animals- 
He states that the lips of young Orangs and Chimpanzees may be pro- 
truded to an extraordinary degree ; they thus act, not only when 
angered, sulky, or disappointed, but when alarmed at anything and like- 
wise when pleased. 
The eyelids are wrinkled, so that a series of grooves, parallel to the 
free margin, exists both in the upper and the lower lid. From the pal- 
pebral margin project well developed eyelashes. The eyes are never 
widely open in the Orang. They are placed very close together ; Fick 
found, in the adult Orang that the pupils were only separated 5.7 cm., 
whilst in the emmetropic human eye they were separated 5.9 cm. 
One of the most characteristic forms of expression in man is produced 
by the wrinkling of the forehead. Apparently the Orang does not pos- 
sess this power to the slightest degree, although several observers have 
found the corrugator supercilii muscles present — muscles which produce 
the wrinkling of the forehead in man. It would appear, therefore, that 
the Orang has lost the power of using these muscles much in the same 
manner as man has lost the power of moving the ears. This lack of 
power of moving the auricle may be commonly noted in man, although 
the muscles in connection with it are developed. The facial muscles of 
expression in general in the ape are poorly developed in comparison with 
the same group in man. Bischoff is no doubt correct when he states that 
man differs from all animals, and from the highest apes very essentially, 
in the strong development and isolation of the facial muscles of expres- 
sion. He concedes that the apes are excellent face-makers, but their 
emotions are expressed by distorting the whole face. The nose of the 
Orang is extremely short and depressed. There is no bridge and no 
point. The anterior nares look upwards and forwards. The shape of 
the ear in the Orang is remarkably like that in man. It possessed, in 
my specimen, the Darwinian pointed tip. This point, to which Darwin 
directed attention, consists of a small blunt process which projects 
inwards from the in-folded margin (the helix). In many monkeys the 
upper portion of the ear is slightly pointed, and the margin is not 
1 Rudolf Pick, “ Verg-leichend anatomische Studien an einen erwachsenen Orang-Utangf.” 
Archiv fur Anat. und Phys. Anat. Abth,, 1895, p. i. 
2 Charles Darwin, “ The Expression of the Emotions in Man and Animals.” London, 1872, p. 140 
3 Charles Darwin, “The Descent of Man.” London. 1871, Vol. I, p. 22. 
