The tongue is composed of bundles of skeletal muscle fibres
At the gross level, there are several muscles that contribute to the formation of the tongue
The orientation of these named muscles in part provides the orientation for the muscle fibres
However, within the named muscles, there may also be a subdivision of skeletal muscle groups which provides for control over the many movements that the tongue carries out
Micrograph of Tongue Muscles:
Skeletal muscle bundles in the tongue
Note that the muscle bundles are not oriented in the same direction