132 



ANATOMY OF VEBTEBRATES. 



fissures, more or less parallel with ?'. The principal folds defined 

 by the above fissures are : a', posthippocampal, k, callosal, //, 

 supercallosal, //, marginal, h', postmarginal, t, falcial, t', subfalcial 

 (which is the inner surface of c, entorhinal), ;/, entolambdoidal, .s-, 

 septal. 



Anthropotomists have primarily divided the hemispheric masses 



118 



Vertical section, half nat. size, Human Brain. XL". 



into groups of convolutions or ' lobes:' some into three, viz., the 

 6 anterior,' e middle,' and ( posterior ' lobes ; others into five. 

 These latter are termed f central ' (lobus centralis), ' frontal ' 

 (lobus frontalis), ' parietal ' (lobus parietalis), ' temporal ' (lobus 

 temporalis}, ' occipital ' (lobus occipitalis}. 



The central lobe (' Stammlappen,' Huschke) answers to the 

 f Insel' of Reil, and is not visible outwardly; it includes the 

 ( gyri breves,' and is, by some, held to be peculiar to Quadru- 

 mana and Bimana (but see figs. 117, 11 8, /',/*'). 



The ( frontal lobe,' fig. 119, r, includes so much of the anterior 

 lobe as lies in advance of the ( frontal fold,' n, n, and is subdivided 

 above into the superfrontal, n' 9 midfrontal, n" ' , subfrontal, n f " ', 

 ectofrontal, ?i x , and ' prefrontal,' % x x , folds : it is an artificial division 

 of the part, most naturally defined, both in Quadrumana and 

 Man, by the coronal fissure, 12, from the rest of the hemisphere. 



