WILLARD: CRANIAL NERVES OF ANOLIS CAROLINENSIS. 79 
that Cords describes a root ganglion, “ganglion jugulare,” for IX 
in addition to the petrosal ganglion. When this appears in a rudi- 
mentary form it is called a somatic sensory structure. If it is large 
enough to be discovered by dissection methods, one might look for a 
cutaneous ramus associated with it. Is it possible that Cords’s 
ramus auricularis VII has any relation to her “ ganglion jugulare” IX? 
The value of Fischer’s (’52) work lies‘in the range of his material, 
which justifies certain deductions, the validity of which might be 
arrived at directly by microscopic study. For comparison with 
Anolis some of the more important statements made by Fischer may 
be considered. This author does not find a root ganglion on IX, al- 
though the petrosal ganglion is to be recognized in practically all cases. 
This ganglion is united with nerve X and joined by rami of larger or 
smaller size, the union with the latter is generally on the proximal end 
of the ganglion through the combined rami communicantes internus 
et externus IX ad VII. In Platydactylus, however, the external 
sympathetic ramus does not join the internal; this leaves, then, only 
the connection to palatine VII known as Jacobson’s anastomosis and 
consequently no apparent connection with the sympathetic system. 
| In another form (Varanus bengalensis) the reverse is true, the internal 
communicating ramus passes [X to join the main sympathetic trunk 
farther distad. A Jacobson’s anastomosis in this case would have to 
go by way of the external ramus. In this form also no ganglion 
| petrosum was discoverable, although it is very large in another species 
|(Varanus nilotocus) of the same genus. Neither Watkinson (:06) 
jnor Osawa (’98) discovered with certainty the petrosal ganglion. 
This would indicate either a scattered condition of the ganglionic cells 
jalong the trunk, or a less developed viscero-sensory component in 
Varanus and Hatteria than exists in the case of Anolis, in which, 
though a smaller animal, it was demonstrable by dissection methods. 
\The failure to find the ganglion by this method would not indicate 
its entire absence. 
The union of [X and X also shows considerable variation, as does 
ikewise the union of these two, combined or separately, with the 
“inain trunk of the hypoglossal. In comparing with all the forms 
{ uitherto described, Anolis may be put down as typical in the combina- 
_ on of the main pharyngeal branches of IX, X, and XII into a common 
-runk, which later separates; but as this union has no significance 
ther than as a common path around the pharynx, it is modified 
yherever there is much variation in shape of head and relative posi- 
ion of parts innervated. In a few cases XII is wholly free, and in 
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