496 



COMPARATIVE ANATOMY 



EPIPHYSIS] .PARENCEPHALON /CHORIOID PLEXUS 

 PARIETAL I / HABENLLftR / POST COM /OPTIC 



CEREBEUJJM 



\ CHORIOlOeA 



IPITAL NERVE 

 SPINAL 



ACCESSORY^ LOBE 



PIRIFORM! 



ANT COM,'*-^ 

 VENTRICLE ID' 



'INFUNDIBULUM 



Fig. All. — Brains of A, a cyclostome (Petromyzon); B, an Elasmobranch (Scymnus); C. a 

 teleost (Cyprinus); and D, an amphibian (Rana) as seen in left lateral aspect. The main 

 fiber tracts and nerves are shown as if projected upon the median plane. Homologous fiber 

 tracts in all figures are given identical numbers. Nervous Pathways of the Brain (fasciculi or 

 tracts). I, olfactory; 2, olfactohabenularis; 3. olfactohypothalamicus; 4, olfactocorticalis; 5, 

 olfactoepistrialis ; 6, olfactopeduncularis; 7. olfactoammonicus; 8, olfactomammillaris; 9, olfactq- 

 amygdalinus; 10, parolfactohabenularis; 11, optic; 12, opticotectalis; 13, isthmoopticus; 14, preopti- 

 cohabenularis; 15, striohypothalamicus; 16, striothalamicus; 17, striomesencephalicus; 18, fasciculus 

 retrofiexus; 19, pallial; 20, hippocampothalamicus; 21, hippocampomammillaris; 22, bulbothalami- 

 cus; 23, bulbocorticalis; 24, frontobulbaris; 25, tectobulbaris; 26, tectospinalis; 27, tectothalamoocci- 

 pitalis; 28, tectocerebellaris; 29, frontothalamicus; 30, frontoepistrialis; 31. corticohabenularis; 

 32, corticothalamicus; 33, corticomammillaris (fornix); 34. corticobulbaris; 35. lobopedunculo- 

 spinalis; 36, habenulointerpeduncularis; 37, habenulocorticalis; 38, mammillotegmentalis; 39, 

 mammillothalamicus; 40, rubrothalamicus; 41. rubrocerebellaris; 42, rubrospinalis; 43, thalamico- 

 spinalis; 44, tegmentocerebellaris; 45, trigemmocerebellaris; 46, quintocerebellaris; 47, septomesen- 

 cephalicus; 48, octavocerebellaris; 49, olivocerebellaris; so, deiterocerebellaris; 51, diencephalo- 

 cerebellaris; 52, mesencephalocerebellaris; S3, vestibulocerebellaris; S4. lateralicerebellans; SS. 

 facialicerebellaris; 56, spinocerebellaris; S7, cerebellotegmentalis; 58, cerebellodiencephahcus; 

 59, spinothalamicus; 60, spinohypothalamicus; 61, octavomesencephalicus; 62, mammdlopedun- 

 cularis; 63, frontobulbaris; 64, lobotectahs. (Redrawn after Plate.) 



