WILLARD: CRANIAL NERVES OF ANOLIS CAROLINENSIS. 69 
demonstrable in VII and are not generally considered present in rep- 
tiles. They are, however, found in the Amphibia (Norris and others), 
and their distribution there would agree quite closely with the reptiles 
if it were discovered that a trace of the cutaneous component were 
carried to the skin in this sympathetic ramus, for the course of this 
ramus is superficial, and anteriorly it anastomoses freely with the 
cutaneous fibersof V. The conditions for study here were not such that 
a failure to observe this would preclude the possibility of a very few 
cutaneous fibers taking this course, should the central relations indi- 
-eate a connection with the somatic sensory tract. The hyomandibu- 
lar just distal to the crossing of the sympathetic divides into the motor 
ramus hyoideus and the sensory chorda tympani (Plate 7, figs. 20, 
21, hy. and cd. tym.). 
(a) Ramus hyoideus (hy.). After parting with its sensory compo- 
nents, the motor part of the hyomandibularis continues its course 
to the muscles supplied by it. As this nerve reaches the depressor 
mandibular (digastric) muscle it divides into two branches for dorsal 
and ventral distribution (Plate 3, figs. 6, 7, hy., and Plate 7, fig. 
23). The final distribution of this nerve is well shown in figure J, 
which is a drawing from a mounted dissection that had previously 
been treated with vom Rath’s mixtures. This shows that the digas- 
tric, sphincter colli, and the most posterior part of the mylo-hyoideus 
are innervated by ramus hyodeus (motor VII). This agrees with 
what Ruge (’97, p. 331) found in Varanus, although Watkinson (:06) 
was not able to discover it in her dissection. 
Ruge (’97), in his extensive monograph on the facial nerve in the 
| vertebrates, considers the mylo-hyoideus muscle in reptiles as belong- 
ing to the innervation field of motor VII, and he finds this demonstra- 
ble in Hatteria (p. 325), where the ventral ramus of VII is figured as 
‘extending almost to the end of the jaws. In the same form the ramus 
mylo-hyoideus of V leaves the jaw in the manner typical of that nerve, 
but Ruge considers it wholly cutaneous sensory.: In the alligator 
jhe same muscle is innervated by the motor fibers carried in the ramus 
mylo-hyoideus of V, and Ruge (p. 381) concludes that V has received 
these “intracranially” from VII. Comparing with the amphibian 
Amphiuma, as described by Norris (:08), the motor components in 
ramus hyoideus VII of Anolis are directly homologous with the ramus 
jugularis of Amphiuma, which innervates the digastric, sphincter colli 
and posterior part of the mylo-hyoideus muscles, leaving the anterior 
part of the mylo-hyoideus to be innervated by the ventral division of 
‘he main mandibular, which is evidently the ramus mylo-hyoideus of 
Y as described in Anolis (p. 61).. 
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