In the giraffe (Giraffa camelopardalis), the masseter muscle was divided into 
several layers. The superficial and more medial (second) tendinous sheets of the 
masseter muscle fused with each other at the dorso-caudal part and a fleshy 
portion was located between these tendinous sheets. In the rostral part, the 
most superficial tendinous sheet turned around as a compact tendon and attached 
to the facial crest (Crista facialis). The turned tendinous sheet, however, 
never fused with the second tendinous sheet and this layer of the masseter 
muscle, that originated from the facial crest with the turned sheet, was 
inserted into the mandible with its fleshy portion. In the cattle, goat, sheep 
and Sika deer, the rostral layer of the masseter muscle arises from the facial 
crest with its fleshy portion and is inserted into the tubercle on the mandible 
through the strong tendinous sheet. In this study, the takin also showed the 
same structure of the masseter muscle. In the giraffe, however, the rostral 
layer inserted into the mandible through the strong tendinous sheet could not be 
distinguished, thus, there was no conspicuous tubercle on the mandible. Moreover 
in the masseteric region of the skull.,the giraffe was similar to the Sika deer 
in several ways. However, it is suggested that the giraffe exerts smaller forces 
on the cheek teeth than does the Sika deer because of its longer Margo 
interalveolaris.