CONVOLUTIONS AND FISSURES OF SURFACE OF CEREBRUM. 57 



the occipital and temporal lobes is fissured mainly in an antoro- 

 posterior direction. A third and fourth temporal suleus is often 

 found. The latter, which extends over into the fi^iipirv.il lobe, 



is called the occipito-temporal fissure. It separates the gyms 

 hippocampi from the convolutions of the temporal lobe. The 

 temporal convolution lying just outside of this fissure (fourth 

 temporal convolution) has received the name of gyms oecipito- 

 temporalis. 



Our knowledge of tlie course of the convolutions comes from 

 Burdach (rnrdian surface), Leuret, Gratiolet, Meynert (com- 

 paratice anatomy), Bischojf, Echer, Pansch (groiriny and adnlt 

 brain}. Besides these there are numerous investigators as to 

 separate localities, e.g., Broca ami Zuckerkandl on the convolu- 

 tion* nrar the margin of the brain, Eberstaller and Guldberg 

 on the island, and Riidinger on the inierpametal fissure. Again, 

 ice possess a considerable number of monographs on the surface 

 of the brain of many mammals. (Anthropomorphous apes, by 

 Bischoff ; lemurs, by Flower and by Gervais ; wliab.-*, by 

 Guldberg; ungulates, by Krueg ; carnivorous animal*, by 

 ^[cynert and Pansch, and many others.} The numerous varia- 

 tions in the course of the individual convolutions and Jjxxt/r^s 

 which may occur in man are not only mentioned by a majority 

 of the above -writers, but have found an investigator of their o/rn 

 in D. Sernow. 



It does not lie within the scope of these lectures, gentle- 

 men, to impart the rich store of facts which physiology lias 

 brought to light respecting the various cerebral structures. 

 Our knowledge of the functions of the cortex is, as yet, in its 

 infancy, and is in no respect complete. I must refer you to the 

 text-books of physiology, in many of which you will find ex- 

 cellent chapters on the subject. In general, it may be said that, 

 so far as the phenomena which follow an injury to the cortex 

 are concerned, more is positively known about human beings 

 than about animals. The following is a short summary of these 

 symptoms : 



