Editorial. 209 



The existence of a cephalic commissure aside from the precom- 

 missure and olfactory decussation (whether one should think of 

 a callosum or not in that connection) is also in point. In other 

 fishes than the teleosts we find still greater evidence that such 

 a consolidation has taken place ; in fact nearly all steps between 

 the ichthic and amphibian brain are now known. This does not 

 necessarily open the question as to the pallium which in spite 

 of the acrimonious discussion it has awakened is really a 

 very narrow morphological problem. Whether the pallium 

 represents the cortex of other groups or whether it is the 

 median plexiform prolongation which in higher forms serves a 

 nutritive function and lies within the ventricle is a question inca- 

 pable of arbitrary solution. The two are continuous and at an 

 early stage are indistinguishable. The distinction can only be a 

 functional one and from a broad morphological point of view 

 is not worth discussing. The great fact remains that the 

 ventricle is enclosed in all forms alike by the product of the 

 embryonic vesicle. To return to our original question. It is 

 seen that in all craniates there is a sensori-motor loop in the 

 cerebrum and that in all forms of which we have sufficient data 

 the tectum is indirectly connected with the pallium or its homo- 

 logon. We venture to differ from Ur. Edinger in his sweeping 

 statement that the olfactory function is the only special sense 

 which enters the psychic life of infra-avian vertebrates but be- 

 lieve that we have evidence which may soon be elaborated to 

 show that reptiles also have their optic associations. However, 

 the interest attaching to Dr. Edinger's generalization is not 

 diminished thereby. In birds, we are told, a large direct asso- 

 ciational tract becomes conspicuous and is correlated with the 

 predominant visual element in their regime. 



C. L. Herrick. 



"^ ^ ^ 



Neurology and Monism. 



The question often obtrudes itself, "Does modern neurol- 

 ogy afford any evidence toward a dualistic construction in psy- 

 chology? " The answer may be both "yes" and "no" and 

 the consideration of the two answers may indicate to some ex- 



