344 MESSRS. F. GOTCH AND V. HORSLEY 



SCHAFER and HORSLEY* noted that bilateral representation of the facial muscles 

 existed in various species of Monkey, but that the trunk and limb muscles were 

 unilaterally represented. 



SCHAFER and MoTrt confirmed these observations. 



BEEVOR and HORSLEY| further showed in more detail that in the Bonnet Monkey 

 (Macacus sinicus) the limbs were unilaterally represented, but that other groups of 

 muscles, e.g., the tongue, buccinator oris, &c., &c., were bilaterally represented in each 

 hemisphere. They discuss this point also in another Paper on excitation of the 

 internal capsule, and confirm the above statement relating to the trunk muscles. 



SEMON and HORSLEY|| have shown that in all animals the vocal cord movements are 

 absolutely bilaterally represented in the excitable area of the cortex ; this bilaterality 

 was previously observed by KRAUSE in the Dog ; it has been contested by MASINI. 



BROWN-SEQUARD! in one experiment on a Monkey found that excitation of the 

 gyrus fornicatus produced movements of the same side of the body, whereas excitation 

 of the paracentral lobule immediately above evoked movement of the opposite side. 



ASCH and NEISSER** found from (but a few) experiments in Rabbits that excitation 

 of the cortex produced movement of the muscles on the same side, and, subsequently, 

 those of the opposite side, whereas excitation of the corona radiata gave movement on 

 the opposite side. The narcosis in their experiments was incomplete. 



CouTYtt occasionally also observed the same phenomenon exceptionally in Rodents, 

 but only in the absence of narcosis. STEFFAHNY^ observed occasionally bilaterality of 

 movement in Rabbits to follow excitation of one hemisphere. BRAUN similarly 

 noted bilaterality in the absence of narcosis. 



2. Excitation Experiments on the Cortex combined with Division of Commissures, 



i.e., Corpus Callosum, &c. 



EXNER|||| observed that in the Rabbit, after section of the commissures, and even 

 after ablation of one hemisphere (see No. 5), bilateral movements (nature not detailed, 

 possibly tonus, p. 189 of his paper), occurred. 



* ' Phil. Trans.,' B., 1888. 



f ' Brit. Med. Jour.,' 1890. 



% ' Phil. Trans.,' B., 1887, 1888, 1890. 



' Phil. Trans.,' B., 1890. 



|| ' Phil. Trans.,' B., 1890. 



^[ ' Comptes Rendus de la Societe de Biologic,' 1887, p. 261. 



** ' Arcliiv fur d. ges. Physiologic,' von PFLUGER, 1887, p. 191. 



ft ' Compt. Rend.,' vol. 96, 1883, p. 506. 



Jl ECKHARD'S Beitrage,' 1888, p. 97. 



ECKHARD'S 'Beifcrage,' 1876, p. 127. 



Jill Wien, Akad. Sitzber.', 1881, 3 Abth., p. 185. 



