riginating on the ventral side. Rooth worked with _Columba
palumbus_, the Woodpigeon, and his description concerned _M. adductor
mandibulae internus pterygoideus_, which is composed of _Mm.
pterygoideus ventralis et dorsalis_ of Lakjar (1926). His assertion
that ventral fibers, that is to say, fibers arising on the ventral
surface of the palatine, insert medially does not appear to be
completely true for doves.

Aponeuroses cover most of the lower surface of the muscle and one or
two nerves extend into the substance of the muscle. The nerves run from
the anterior edge of _M. pterygoideus dorsalis medialis_ and farther
posteriorly from a separation in the muscle.

~_M. pterygoideus ventralis medialis._~--The origin is by aponeurosis
from the ventral surface of the palatine and fleshy from the palatine
fossa. The aponeurosis is the same that gives origin to the fibers of
_pars lateralis_. Part of the aponeurosis becomes tendonlike in the
middle of _M. pterygoideus ventralis_ and separates its two divisions.
The insertion is fleshy on the lower one-third of the anterior surface
of the internal angular process of the lower mandible, and by two
tendons on the distal tip of that process. Many of the fibers of _pars
medialis_ insert on the tendons. The fibers at their insertion are not
distinctly separate from those of _pars lateralis_ and there is
considerable mingling of the fibers. Consequently, the medial part of
_M. pterygoideus ventralis_ cannot be removed as a part distinct from
the lateral part (figs. 1, 4, 10, 21 and 22).

Ordinarily _M. pterygoideus ventralis_ does not cross the ventral edge
of the lower mandible, but in one white-wing the muscle was slightly
expanded on the right side and it could be seen in lateral view. The
homologous muscle in _Columba palumbus_ apparently is consistently
visible in lateral view. (See Rooth, 1953, fig. 6.)

~_M. pterygoideus dorsalis medialis._~--The origin is fleshy on the
dorsolateral surface of the palatine immediately anterior to the
pterygoid and also on the anterior, dorsolateral, posterior and
ventromedial surfaces of the pterygoid. The insertion is fleshy on the
ventromedial surface of the lower mandible and the anterior surface of
the internal angular process immediately dorsal to the insertion of _M.
pterygoideus ventralis lateralis_.

~_M. pterygoideus dorsalis lateralis._~--The origin is fleshy from the
dorsolateral surface of the palatine, anterior to the origin