266 Cc. JUDSON HERRICK 
olfactory organ of vertebrates adapted for life on land,” an un- 
tenable position which he unfortunately attempted to support 
by a reference to the nervus terminalis which reveals a total 
neglect of the recent contributions dealing with the innervation 
of this region. 
The Anura possess a well-developed vomeronasal organ in 
typical position with a specific vomeronasal nerve related to a 
specific part of the olfactory bulb, which in turnis connected with 
the amygdala by a specific olfactory tract. It is strongly sug- 
gested that the emergence of a morphologically circumscribed 
amygdala in Anura is directly correlated with the specificity of 
its physiological relation with the vomeronasal organ. 
All of the fiber-tract connections of the anuran amygdala are 
probably present in some form in urodeles—certainly the most 
important ones are clearly recognizable. In urodeles these 
fiber systems converge into a single non-specific “ventrolateral 
nucleus.” It is not improbable that in the more highly differenti- 
ated brains of different types of fishes some of these elements are 
present but dissociated in various ways. In the Anura the inte- 
grating factor which has brought these elements together into a 
single correlation mechanism and detached this center from the 
more generalized ventrolateral nucleus of the ancestral form seems 
to be the vomeronasal organ, for this specific connection is the only 
obvious physiological factor which is added in the anuran brain. 
If, as suggested by Seydel and others (p. 214), the vomeronasal 
apparatus was differentiated in connection with the opening of 
the posterior nasal aperture and the consequent passage of 
olfactory media from the mouth cavity into the nasal sac, it is 
obvious that from the beginning of this evolutionary process an 
intimate physiological relationship existed between olfactory 
excitations of this type and the gustatory excitations arising 
within the mouth cavity. 
Our knowledge of the ascending gustatory path in the brains 
of vertebrates is very meager. In teleosts it has been shown 
(Herrick, ’05, p. 415) to pass from a reflex correlation center in 
the isthmus region (the Rindenknoten of Mayser, superior 
secondary gustatory nucleus of later authors) to the region of the 
