Johnston, Forchrain Vesicle in Vertebrates. 525 



in mammals (e. g., cortex lobi pyriformis). Elsewhere Kappers 

 insists npon tertiary afferent pathways as the essential criterion of 

 the cortex. The use of two different criteria at different times leads 

 to confusion of thought. I would not apply the term cortex or 

 pala?ocortex to these secondary olfactory cei^ters, but Avould use the 

 simple terms lohus olfactorius, lobus pyriformis, etc. I would apply 

 the term cortex to certain functional mechanisms. The above sugges- 

 tions toward the definition of these mechanisms are of necessity incom- 

 plete and in part hpyothetical. If such a term as palteocortex were 

 used it should be applied to the morphological forerunner (homologue) 

 of the true cortex. 



S. Divisions and Nomenclature. The nomenclature of the brain 

 adopted by the Basle commission is still the best that we have, 

 largely because it embodied the results of the indefatigable work and 

 keen insight of His. Before suggesting certain changes in the 

 BNA tables to bring them into accord with the facts I wish to 

 examine briefly the nomenclature offered by some recent authors. 



Edinger has shown great fertility and enterprise in the production 

 of new names in brain anatomy. Edinger's terms have arisen from 

 his comparative studies of adult brains and are the expression of his 

 effort to present large and obvious relationships in attractive form. 

 He considers the lamina terminalis as the ant^-rior boundary of the 

 diencephalon, agreeing with the BI^A. The narrow portion of the 

 brain extending forward from the optic chiasma (very long in Chim- 

 iera) he calls the pra'thalamus (1908, p. 194). ^\Tien he comes to 

 describe the telencephalon (p. 251) he describes the lamina terminalis 

 as the plate which unites the two halves of the telencephalon. He 

 treats the anterior commissure system as belonging to the telen- 

 cephalon and even speaks of the ''recessus prsechiasmaticus" as one 

 feature of the telencephalon. Here is a contradiction for which 

 there is no remedy in Edinger's mode of treatment. The difficulty 

 is augmented by Edinger's definition of the primitive basal portion 

 of the telencephalon (hypospha>rium) : the primary and secondary 

 olfactory centers and the corpus striatum. Now the floor of what 

 Edinger calls prnethalamus is a secondary olfactory center which I 

 have called the nucleus prteopticus. It receives fibers from the bulbus 



