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 ^•alue 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 hmgalensis) the reverse is true, the internal 

 communicating ramus passes IX 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 

 (J^aranus nUotocus) of the same genus. Neither Watkinson ( :06) 

 nor Osawa ('98) discovered with certainty the petrosal ganglion. 

 This would indicate either a scattered condition of the ganglionic cells 

 along 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 IX and X also shows considerable variation, as does 

 likewise the union of these two, combined or separately, with the 

 main trunk of the hypoglossal. In comparing with all the forms 

 hitherto described, Anolis may be put down as typical in the combina- 

 tion of the main pharyngeal branches of IX, X, and XII into a common 

 trunk, which later separates; but as this union has no significance 

 other than as a common path around the pharjVTix, it is modified 

 wherever there is much variation in shape of head and relative posi- 

 tion of parts innervated. In a few cases XII is wholly free, and in 



