THE MAMMALIAN NERVOUS SYSTEM 105 



(1) Stria olfactoria lateralis (radix lateralis bulbi olfac- 

 torii). This can easily be dissected out, following the fissura 

 rhinalis from the olfactory bulb to the tip of the gyrus hippo- 

 campi (lobus hippocampi, lobus piriformis). In the human 

 brain it runs farther lateralward in the lateral fissure to the 

 border of the insula and then bends sharply medialward and 

 backward to enter the uncus of the temporal lobe. 



(2) Stria olfactoria medialis (radix medialis bulbi olfac- 

 torii) . This can be dissected out and will be found to ascend 

 on the median surface of the hemisphere and to terminate 

 chiefly in the medial olfactory area under the genu of the corpus 

 callosum. This area includes the gyrus subcallosus and 

 septum. 



(3) Stria olfactoria intermedia. This lies between the me- 

 dial and lateral striae. Part of it can be dissected out directly 

 into the anterior commissure (Burkholder ('12), Plate XIX), 

 within which it decussates to terminate in the anterior perfor- 

 ated space (tuberculum olfactorium) of the opposite hemi- 

 sphere. This tract can best be dissected by locating the 

 anterior commissure on the median surface of the specimen and 

 then teasing its fibers out as they pass lateralward and forward 

 toward the olfactory bulb. (The anterioj commissure contains 

 other fibers besides these, some of which pass between the 

 corpora striata of the two hemispheres and others enter the 

 stria terminalis; see Sections 125 (5) and 132.) A second part 

 of the stria olfactoria intermedia, composed of more scattered 

 fibers, terminates in the region of the anterior perforated space 

 of the same side. 



124. The area olfactoria. This area includes the terminal 

 nuclei of the olfactory tracts mentioned in the preceding 

 section. 



The area olfactoria lateralis includes the gray matter accom- 

 panying the lateral olfactory tract, or the lateral olfactory 

 nucleus (termed by Retzius in the human embryo, lateral 

 olfactory gyrus; see Herrick ('18), Fig. 105), and the part of the 

 temporal lobe reached by the lateral olfactory tract (region of 

 the uncus) and the amygdala. Cf. Section 126 (3). 



The area olfactoria medialis includes the gyrus subcallosus 

 (pedunculus corporis callosi), area parolfactoria of Broca and 



